About this Wiki
The E39 Wiki should be used as a tool to help all E39 owners. The greatest feature of the Wiki is that anyone with an account on Bimmerfest has the ability to edit it. If you see something incorrect or notice something missing, simply click on the edit link to the right of any section. Please respect the contributions made by other members.
The E46 wiki has a lot of information, and the I6 engines are largely shared with the E39. If the answer to your question is not here, have a look over there. Also, check out the E39 "Best Links" thread and wiki.
Many thanks to Bluebee, whose tireless efforts cataloguing E39 information created the foundations for this wiki.
The E39 was produced from 1995 to 2004. It was the successor of the E34, and was replaced by the E60. Sales to Germany and the United Kingdom began in 1995, and by 1996 sales to the rest of the world had commenced. The design draws heavily from the E38 7-Series in body construction, v8 engines and electronic technology. Also, many elements (including the 6 cylinder engines) are shared with the E46 3-series.
In the US, the E39 was launched with the 528i and 540i models. The 528i uses the 2.8 litre M52 inline six cylinder engine from the E36 328i, and the 540i uses with the 4.4 litre M62 V8, shared with the E38 740i. In addition to these models, Europe and some other markets received the 520i (2.0L M52), 523i (2.5L M52) and 535i (3.5L M62) petrol models. The diesel models also initially offered these other markets were the 525td (2.5L M51 turbodiesel inline six) and 525tds (525td engine with intercooler). "Individual" cars have interior and exterior colours that are not available in the standard model range.
The M5 variant was introduced in 1998, using the 4.9 litre S62 V8 engine. The M5 is only available as a sedan.
The V8 models were upgraded in September 1998 to the M62TU engine, which features single vanos and electronic throttle. Similarly, the six-cylinder petrol engines were upgraded to the M52TU engine in September 1998. Also in September 1998, the touring body style was released and stability control was upgraded from ASC to DSC.
The major update ("LCI") appeared in September 2000 for the 2001 model year. The major changes are:
- 525i (M54) replaced 523i (M52TU)
- 530i (M54) replaced 528i (M52TU)
- 520d was introduced, using the M47 four-cylinder turbodiesel.
- 525d (M57) replaced 525td (M51)
- 525tds (M51) was discontinued
- 530d (M57) had a slight increase in power
- V8 engines were unchanged
- All models received "angel eye" headlights, LED tail-lights, widescreen navigation and various detail changes.
In 2003, the limited edition 540i M-sport model was produced.
|Model||Engine||Displacement (cc)||Bore/Stroke (mm)||Comp. ratio||Power (kW/bhp)||Torque (Nm/ft-lb)||0-62mph (manual)||Years||Where sold|
|520i||M52||1991||80/66||11.0||110/150 @6250RPM||190/140 @4200RPM||10.2sec||1996-1998||Non-US|
|M54||2171||80/72||10.7||125/168 @6100RPM||210/150 @3500RPM||9.1sec||2000-2003|
|523i||M52||2496||84/75||10.5||125/168 @5500RPM||245/181 @3950RPM||8.5sec||1995-1998||Non-US|
|525i||M54||2494||84/75||10.5||141/189 @6000RPM||245/181 @3500RPM||8.1sec||2000-2003||Worldwide|
|528i||M52||2793||84/84||10.2||142/190 @5500RPM||280/210 @3950RPM||7.5sec||1995-1998||Worldwide|
|530i||M54||2979||84/89.6||10.2||170/228 @5900RPM||300/220 @3500RPM||7.1sec||2000-2003||Worldwide|
|535i||M62||3498||84/78.9||10.0||173/235 @5700RPM||320/236 @3300RPM||6.9sec||1996-1998||Non-US|
|M62TU||180/241 @5800RPM||345/254 @3500RPM||1998-2003|
|540i||M62||4398||92/82.7||10.0||210/282 @5400RPM||440/320 @3900RPM||6.2sec||1996-1998||Worldwide|
|M62TU||218/282 @5400RPM||440/320 @3600RPM||1996-2003|
|M5||S62||4941||94/89||11.0||294/394 @6600RPM||500/370 @3800RPM||5.3sec||1998-2003||Worldwide|
|Model||Engine||Displacement (cc)||Bore/stroke (mm)||Comp. Ratio||Power (kW/bhp)||Torque (Nm/ft-lb)||0-62mph (manual)||Years||Where sold|
|520d||M47||1951||88/84||19.0||100/134 @4000||280/210 @1750RPM||10.6sec||2000-2003||Some European countries|
|525td||M51||2497||80/82.8||22.0||114/185 @4800||230/170 @1900RPM||11.9sec||1997-2000||Europe|
|525tds||105/141 @4000||280/210 @2200RPM||10.4sec|
|525d||M57||17.5||120/161 @4000||350/260 @2000RPM||8.9sec||2000-2003||Some European countries|
|530d||2926||84/88||18.0||135/181 @4000||390/290 @1750RPM||8.0sec||1998-2000||Europe|
|142/193 @4000||410/302 @1750RPM||7.8sec||2000-2003|
Differences between engines
Early 6-cylinder petrol models use the M52 (non-TU) engine. The M52TU has many differences to the M52, such as Dual Vanos and electronic throttle (with mechanical backup). In 2000, the M52TU was replaced by the M54. The M54 engine is very similar to the M52TU, with only a few changes such as fully electronic throttle, a non-return fuel system and an electronic thermostat.
Early v8 models use the M62 engine. The later M62TU has several differences to the M62, including the addition of Single Vanos, electronic throttle and a water-cooled alternator.
The E39 generally follows the traditional BMW model naming convention. The first number represents the platform (5 Series), the second is the engine capacity (litres times 10) and the letter is the engine type.
Engine types are as follows:
- i - Petrol engine (historically, the letter i means "electronic fuel injection")
- d / td / tds - Turbodiesel engine
Therefore a 525tds has a 2.5 litre turbodiesel engine, and a 535i has a 3.5 litre petrol engine.
Exceptions to the naming convention are:
- 520i models after September 2000 have a 2.2 litre engine
- 523i models use a 2.5 litre engine
- 540i models use a 4.4 litre engine
Oil and filter change
Like most cars, the typical method of removing old engine oil is by removing the sump plug ("gravity draining"). Some people like to use an extraction pump (cnn thread) or "vacuum extraction" (cn90 thread, Bluebee thread) instead.
For choosing which oil to use, BMW recommends "LL-01 Approved" (aioros thread) for the E39. There is a wide variety of oils used by owners, and the topic is the subject of much debate (bluebee thread, jnyost thread, brandon002 post).
The oil service indicator (SI) light can be reset without any tools (mr-fix video).
Low engine oil pressure can cause engine damage. The red "oil can" warning light on the dash indicates that oil pressure is low, therefore running the engine may cause damaged. Rattle at start-up (often assumed to be due to Vanos) can be caused by a faulty oil filter housing or check valve in the oil pump (1, 2).
- Discussion about causes of low oil pressure: toofast02 thread
Oil level and oil consumption
As opposed to the red "oil can" light (see above), the yellow "oil can" warning light merely indicates that the oil level is one quart low (fudman post), which does not present an immediate risk. To accurately measure the oil level, the dipstick should be used (dcolangelo thread). Very low oil can cause ticking sounds (rikshot thread) and risk of major engine damage.
In E39 petrol engines, it is common to need a 0.5 litre top-up of oil between oil changes (brandon002 post), which is possibly due to CCV problems (vavet5308 thread). The BMW dealership information (TIS) states that up to 0.7 litres per 1000 km is normal consumption. Excessive oil consumption is likely due to an oil leak or oil burning, and should be investigated (Energizedmortal post). If the spark plugs are oily, the common causes are CCV, valve guides and piston rings (Wgosma post).
Discussion about dipstick calibration: fudman thread
Oil filter housing
The gasket at the bottom of the oil filter housing is a common cause of oil leaks (1).
The freeze plug (also known as Welch plug) is also a possible cause of oil leaks (1- see second half of past).
Oil pan gasket
The oil pan gasket is a potential source of oil leaks, however in many cases the leak has actually been caused by the oil filter housing gasket (1). The official procedure for the M52/M54 involves dropping the subframe, however it is possible to avoid this by cutting the new gasket into pieces (2) or RTV sealant (3).
Valve cover gasket (VCG)
A common source of oil leaks. Leaks can be caused by poor sealant, cracking and occasionally a warped valve cover (1).
- M52 procedure: Pelicanparts, Millertimebmw video
- M54 procedure: mkodama thread, Bimmer Zeit video
- M62 procedure: ArbysNight thread, Scotmm thread, stas thread
- Discussion about sealant: sealbeach740 thread
A failed head gasket can cause the coolant, exhaust gasses and/or engine oil to mix. Options to check for head gasket failure (and/or cylinder head damage) are a chemical test (also known as "block tester") for combustion gasses in the coolant, compression testing the cylinders or pressure testing the cooling system (1, 2, 3, 4).
Head gasket replacement procedure: Jackcat559 thread
Crank case ventilation valve (CCV)
A failed CCV (sometimes called "positive crankcase valve" or "oil separator valve") is a common cause of poor running (due to vacuum leaks) or high oil consumption (bluebee thread, RDL thread). . The valve itself can fail (jfive96 thread), the associated hoses can leak and the dipstick tube can become clogged (blueebee thread). Some people have replaced the CCV with an oil catch can (eparayno thread). Replacing the CCV is a large job, and easier to do with the intake manifold removed (BavarianE31 thread).
The tube from the CCV to the dipstick can become clogged (blueebee thread).
There is a special "insulated" CCV to prevent failures in cold weather due to condensation freezing (kjet540 post).
Timing chain tensioner and guide rails
A failed timing chain tensioner can cause a rattling noise, initially on startup and then constantly as the problem gets worse. If the timing chain slips due to failure of the tensioner or guide rail, this could result in extensive engine damage. Timing guide rail failures are more common on v8 engines, particularly after 150,000 miles (Mkjs thread, edjack post). The M62TU timing chain system is different to the M62, however both versions have experienced failures (Mkjs post).
M54 replacement procedure: doru thread
M54 removal procedure: Jackcat559 thread
M62TU replacement procedure: blackBMWs thread
VANOS is a type of variable valve timing, which advances and retards the camshaft. Single-VANOS (exhaust camshaft only) is used on the M52 (non-TU) and M62TU engines. Dual-VANOS (intake and exhaust camshafts) is used on the M52TU, M54 and S62 engines.
The seals used by BMW seem to have a limited lifespan, and once they fail the VANOS does not function correctly. This can cause rough idle, stalling and loss of power (ca2014mp2 post). The VANOS can be tested using DIS (TheHockeytowner thread). Many users recommend upgrading to seals made from Viton, such as those sold by Beisan Systems (bluebee thread).
Rattling sounds can be caused by failed VANOS bearings, and there are kits available to rebuild the VANOS unit using new bearings.
As an alternative to using a kit to replace the seals and/or bearings in a VANOS unit, refurbished VANOS units can be purchased from Dr Vanos (Fudman post). BMW does not provide the VANOS seals separately. It sells rebuilt VANOS units for ~$500. According to Beisan Systems (who sell the aftermarket Viton seals), BMW's rebuilt VANOS units are supplied with the same o-rings and have been found to fail in 20,000 miles.
M52 (non-TU) seal replacement procedure: Beisan Systems
M52 (non-TU) bearing replacement procedure: Beisan Systems
M52TU / M54 seal replacement procedure: Beisan Systems
M52TU / M54 bearing replacement procedure: Beisan Systems
M52TU / M54 VANOS replacement procedure: Pelican Parts (eg installing a new or refurbished VANOS unit)
Valley Pan gaskets
On the M62 engine, the valley pan gaskets can leak coolant. If the gasket has failed, coolant build-up may be visible in a recess of the valley pan (). However, a Rear Coolant Plate leak has similar symptoms (2).
OBD fault codes
Scanning the fault codes is recommended as a starting point for many problems. Fault code(s) will be stored when the Check Engine Light (CEL- an orange light on the dashboard) is lit. However, there are also many fault codes which do not cause the CEL to be lit. Scan tools- some of which also can reset service lights- are available from a range of suppliers (1).
Fault codes are a valuable clue to diagnosis, but often should not be taken literally. For example, there are many possible causes of a MAF fault code other than a fault with the MAF itself. Similarly, the "cylinder misfire" code cannot always be taken literally. This code is set by the crank angle sensor detecting fluctuations in engine speed as each cylinder combusts (3). The misfire code is determined from a "smooth running test" (also known as "true running test") value for each cylinder, which some scanning tools are able to read. Problems affecting a single cylinder are easily identified using the misfire code, however if multiple cylinders are affected the misfire codes can be misleading.
The E39 uses OBD version 2 (OBD2). Early E39s have the round port under the bonnet, late E39s have the rectangular plug in the cabin, and some E39s have both plugs. For cars with both plugs, the rectangular plug can only report engine and transmission information, however by jumpering certain wires the rectangular plug can communicate report information from all modules (2).
- Fault code translation: Bluebee thread, obd-codes.com, myscantool.com
- General OBD2 information: NAPA pdf
- Discussion about smooth running test: VitaminXX thread, Patrick Houston thread
OBD live data
Some OBD readers can provide realtime readouts of engine conditions, which is similar to the Secret Menu, but more includes more detailed information such as fuel trims and oxygen sensor readings. This information can be helpful when troubleshooting engine problems.
OBD live data reference values: TheAngryBear thread
Fuel trims (LTFT and STFT)
The Long Term Fuel Trim (LTFT) and Short Term Fuel Trim (STFT) indicate whether the engine is increasing or reducing the amount of fuel used, to compensate for something. Reading these trims can provide helpful troubleshooting information.
Engine failsafe error
An "engine failsafe" error means the engine is running in "limp home" mode, due to failure of a critical component. Possible causes include the throttle body (540_M-sport thread, 540VIspeed thread), a blown fuse (Oscswa thread, peetiewonder post), low voltage due to battery/alternator (cgill22 post, LinGG post). However there are many possible causes, so start to narrow down the problem by checking battery voltages and OBD fault codes (Dnell86 thread).
The official specification is for spark plugs should be replaced every 100,000 miles (Bluebee post) or when showing signs of wear; however some people prefer to change them more often, eg every 50,000 miles (cn90 post). Using the correct spark plug means the gap size is already correctly set; the gaps are not meant to be adjusted on the spark plugs used by E39s (Ryan M post). Checking the condition of the spark plugs ("reading the plugs") gives useful information about how that cylinder is running (ngksparkplugs.com, procarcare.com, onallcylinders.com).
The specified spark plugs are:
- M52: Bosch F8LDCR
- M52TU: Bosch FGR7DQP or NGK BKR6EQUP
- M54: Bosch FGR7DQP or NGK BKR6EQUP
- M62 until 7/97: Bosch F7LDCR or NGK BKR6EK
- M62 from 7/97: Bosch F9LDCR
- M62TU: Bosch FGR7DQP or NGK BKR6EQUP
Discussion about using single prong NGK Iridium plugs: cn90 post,
All E39 petrol engines use an ignition coil located above each spark plug ("coil on plug"). Lifespan of ignition coils vary greatly, but failures become more common at higher mileage (jieg thread). This can lead to rough idle and a lack of power (Andlloyd thread) and sometimes triggers a misfire fault code for the cylinder.
To troubleshoot a single faulty ignition coil that is producing an error code, start by swapping the coils between cylinders and seeing if the error code changes cylinders. Coils can also be tested using an oscilloscope (Jase007 post).
A worn "spark plug boot" is sometimes the cause of ignition faults (540 M-sport post). A replacement spark plug boot is much cheaper than the whole ignition coil assembly.
Discussion about quality of various brands: NY_98_528i thread
Camshaft Position Sensor (CPS)
A faulty CPS can cause a lack of power, stalling and hard starting (Poolman thread). Failures of the CPS is common problem (Edjack post). Often a faulty CPS will not cause a fault code. It is recommended that a genuine BMW/VDO part is used (ca2014mp2 post).
Crankshaft Position Sensor (CKP)
Failures of crankshaft position sensors seem to be rare, however in one reported case it resulted in stalling, hard starting and the Crankshaft Sensor fault code being triggered (Girtho thread).
M52/M54 location: barneyhyphen thread
M62 replacement procedure: zapperjoe thread
Cruise control actuator
On engines with a mechanical throttle, a broken cruise control actuator can be a cause of cruise control problems.
Repair procedure: MontanaRob thread
A faulty alternator means the battery is not charging properly, therefore it will cause flat batteries. A properly functioning alternator will measure 14.4 volts while idling at full electrical load (Burning2nd post).
Instead of replacing the alternator, it can often be rebuilt (cn90 thread, airos thread, oichan.org). On an air-cool alternator, the air duct should be cleaned of debris such as leaves (cn90 thread, Neversaynever thread).
E39s were fitted with 90 Amp, 120 Amp or 140 Amp alternator. The type of alternator fitted to a car can be identified from the sticker (bluebee thread). However, the M62TU uses a water-cooled alternator (verite thread), and often auto-electricians are not willing to rebuild it. However it is possibly to DIY rebuild this alternator (RocketSurgeon thread).
M52 replacement procedure: flybot thread
M54 replacement procedure: M54 Alternator DIY Video
A failing battery can cause many strange problems with the car, therefore it is often worth checking the battery voltage as a first step. Before disconnecting the battery, some people prefer to wait until the car has gone into "sleep" mode (1), however some people consider this unnecessary. A normal cranking speed does not necessarily indicate that the battery is fine (2).
To prevent the build-up of gasses in the truck, the vent tube should be used (3).
- Battery test procedure: Bluebee thread
- Replacement procedure: jamesdc4 thread
- Procedure for topping up the distilled water: BMWdiy
A common cause of flat batteries is current drain, however first test the battery to ensure that it is not simply that the battery is too old. Common causes of current drain are a faulty FSU (bluescholars thread), the car is not going into sleep mode (check if light indicating gear on shift lever is out after 20 min without opening doors), the CD changer constantly cycling disks after the car is turned off, or the navigation system.
Fuses and relays
Failure of the fuel filler door locking solonoid can cause the fuse for the rear door locks to blow (kiwijochen thread).
Poor connections on these straps, including the one located under the cabin air filter (djt5150 thread), can cause various electrical problems.
Ground locations: JimLev post
Warning: the temperature gauge on the dash is heavily buffered and may not show that the engine is overheating until it is too late (1, 2t, 3, 4). Therefore, as soon as the needle moves beyond halfway, turn off the engine to minimise damage.
The coolant temperature can be checked in realtime using the OBC "secret menu" (5). A coolant level sensor is only present on cars with the High OBC (6). The manual method of checking coolant level is using the float in the expansion tank.
When draining or flushing the coolant, it is suggested to disconnect the lower radiator hose instead of using the drain plugs (7).
- Overhaul procedure: CNN-090 thread, CNN-090 post, bluebee post
- Discussion about date stamps on cooling components: speedgoat thread
- Discussion about quality of various brands: drewdane thread
A cooling system which is not properly bled can suffer sporadic rises in temperature or loss of cabin heat. The BMW TIS has some specific notes about bleeding the cooling system (NNY528i thread). Some people prefer to replace the plastic bleed screws with brass screws (Mack thread).
M54 drain plug location: bluebee thread
Removal of the fan shroud (and fan) is often required to work on components at the front of the engine.
Fan / fan clutch
The thermostat regulates the coolant temperature by routing coolant through the radiator when required. A failed thermostat can cause an engine to run cold(1), or (much worse) overheat.
The E39 uses an electronic thermostat, which causes the engine to run hotter or colder based on engine load. A supplier of non-electronic E39 thermostats claims that the electronic map-controlled can cause cooling system failures (2).
- M52 replacement procedure: bmwtips.com
- M62 replacement procedure: joshs540i thread, pelicanparts.com
- O-ring replacement discussion: bluebee thread 1
- Operating temperature discussion: bluebee thread 2
Radiator and expansion tank
The plastic parts within the radiator and expansion tank are common causes of leaks as the parts age (bluebee thread). Some people use an all-aluminium radiator instead of the OEM part.
When removing radiator hoses, the plastic clips are fragile and should be leveraged apart using minimal force (bluebee post).
Coolant level sensor discussion: bluebee thread
Outlet temperature sensor replacement procedure: pelicanparts.com
Radiator cap and system pressure
Some people believe that the high pressure of the BMW cooling system contributes to failures, and therefore install a lower pressure radiator cap (540IA_750IL thread). The lower pressure cap does not affect normal operation, since the system spressure is below 1.4 bar anyway at normal operating temperatures (Gary@GAS post, JimLev post). The difference is that, if the engine overheats, the system vents pressure earlier.
A few people have used a waterless cooling system (chiefwej thread).
Temperature gauge on dash
The temperature gauge is not linear and the 12 o'clock position seems to cover a large range of temperatures (windsmith post, sixpot_simon thread). There are reports of a warning bell sound when the engine is overheating (540iman thread).
The temperature gauge can be recoded to show a more linear reading, to give more warning of overheating (Mr.Philadelphia thread).
Discussion of replacement options: bluebee thread
Replacement procedure: pelicanparts.com
This electric fan operates on low speed when the air-conditioning is used. It also operates at medium and high speed as required to assist in cooling the engine. Failure of the fan itself or fuse #75 (cnn post) are common causes for the fan to not operate correctly. For 1997-1998 models (cn90 post), a replacement fan motor is available (PENER thread 1).
The drive belts (also called serpentine belts) provide power to ancillaries such as power the water pump, alternator, air-conditioning compressor and power steering pump. The belts can crack as they age, eventually leading to failure (which can cause the engine to overhead since the water pump stops working). Special tools to hold the rotating parts in place can be either purchased, created or improvised (bluebee thread).
M54 replacement procedure: bluebee post
M62 replacement procedure: ArbysNight thread
Discussion about diagnosing belt squeal: bmw4te thread
Fuel and intake
Vacuum leaks are one of the most common cause of engine problems (ca2014mp2 post). Symptoms vary, however they can include poor idle, a P0171 error code, lack of power and other symptoms. Sources of vacuum leaks include the intake elbow, CCV, DISA and their associated hoses (poolman thread,Bluebee thread 1, 2, 3).
Common methods of troubleshooting vacuum leaks are:
- Reading the fuel trims (see fuel trims section)
- Spraying carburettor cleaner around the intake hoses while listening for a change in idle speed (Gmak2012 post, Helmet75 post, ca2014mp2 post)
- The "oil cap bag test" (Bluebee post).
- Measuring inlet vacuum, using the port at the rear of the intake. For the M54 engine, a reading of 18+ inches of water (with the airconditioning off) indicates healthy intake vacuum (F1Jim64 post).
- A smoke test (ca2014mp2 post, Johnstern post). Some people claim this is the definitive test for vacuum leaks, however it requires a smoke machine. Check for leaks at the brake booster, secondary air system and exhaust (ca2014mp2 thread).
Also called "intake boot".
Idle control valve (ICV)
A faulty ICV can cause poor idle and stalling. The valve can become clogged with carbon deposits or can have electrical problems. Note that the resistance specification published in the Bentley manual for six-cylinder engines is incorrect (1, 2)
For a rough idle which is not showing any fault codes, the problem can occasionally be due to a damaged rotating component- such as the cooling fan or flywheel- that is upsetting the engine's rotational balance (3).
M62 cleaning procedure: John540i6 thread
This valve allows different length intake runners to be used, increasing torque at low revs. The main risk with the DISA is that worn parts can become loose (teklord69 thread 1) and get ingested into the engine, causing catastrophic damage to occur (ForcedFirebird post). An aftermarket DISA valve which is redesigned to remove the possibility of a worn pin being ingested into the engine, is available (Gary@GAS thread).
Other possible DISA problems failure can be caused by the valve becoming clogged, the plastic cracking, a failed O-ring (brickwhite thread) or the diaphragm rupturing (uncmozo thread, dakarm thread). A failed DISA valve can cause a rattling sound (Bimmer Zeit video).
Failed DISA autopsy: teklord69 thread 3
Discussion about diagnosing DISA failure: bluebee thread
A clogged fuel filter can cause trouble starting, loss of power and stalling (the same symptoms as a faulty fuel pump).
For 6-cylinder cars, the M54 fuel filter is different to the M52 filter, due to the addition of a pressure regulator (cn90post).
Autopsy of used fuel filters: Nervous thread
Discussion about fuel filters: dalekressin thread
Fuel pump & fuel pressure regulator
A lack of fuel pressure can cause trouble starting, loss of power and stalling (redbull713 thread, agarch92 thread, cwp01 thread). A faulty fuel pump is a common cause, however, lack of fuel pressure can also be caused by a faulty Fuel Pressure Regulator (FPR) or fuel filter.
Relay location: bluebee thread
Discussion about low fuel pressure and error code 1250: JEREMYZ thread
Fuel level sensor
A faulty fuel level reading is commonly due to a failed fuel level sensor (also called "fuel gauge sending unit"). After replacing the sensor, it is necessary to run Test 21 to reset the dash gauge (QSilver7 post).
Fuel tank vent hose
The smell of fuel in the car can be caused by a fault with the fuel tank vent hose (Chillebeam thread).
Mass Airflow Sensor (MAF)
A faulty MAF can cause rough idle and poor fuel consumption. Note that a MAF error code can also be caused by a problem elsewhere in the engine (eg CCV, intake leak). Over time, the sensor can become dirty and requires cleaning.
Typically, a faulty MAF will cause the engine to run rich. However, poor performance due to running very lean has also been observed as a result of a faulty MAF (F1Jim64 post). In this case, no MAF error code was present.
A test for MAF accuracy is the fuel consumption readout (which can be accessed using the Secret Menu). Note that the test should be conducted with the aircon off (F1Jim64 post 1), auaq thread, F1Jim64 post 2).
Leaking injector seals can cause leanness or fuel leaks (1).
For 530i cars in cold climates, old injectors can distort and cause fuel leaks (2).
After de-pressurising the fuel rail (such as removing fuel injectors) the engine might need cranking for a while until the fuel returns to the rail and the engine starts (1).
A loose gas cap can cause a Check Engine Light (IH8DMV thread).
Throttle position sensor (TPS)
Oxygen sensors (O2 sensors)
A faulty oxygen sensor can cause poor fuel economy. The sensor can be tested by reading the OBD2 "live data" (ca2014mp2 post) or using a multimeter (Edwin thread). Failure of the heater in the oxygen sensor can cause a fault code (acoste post).
Tools required for M54 oxygen sensor replacement: Bluebee thread
Procedure for M62 oxygen sensor replacement: BMWtips
Secondary Air System
Problems with the Secondary Air Pump (SAP) can cause fault codes or thumping sounds (16valex thread). The failure can be the pump itself (cn90 thread), the valve (cn 90 thread) or the vacuum hoses connected to it (fudman thread). The pump and valve can be rebuilt (cnn thread).
Secondary Air System troubleshooting and repair: vtxpower thread
Repair procedure for rattling heatshield: cn90 post
If a catalytic converter ("cat") has failed, it will increase exhaust emissions. A clogged cat increase exhaust back-pressure, causing loss of power and perhaps other symptoms. Sometimes a faulty O2 sensor is incorrectly diagnosed as a faulty cat (Schnell5 post).
Discussion about replacement cats: mtnAVman thread
Japanese E39s have a warning message "SLOW! CAT. OVERHEAT" for when the catalytic convertor is overheating due to a rich mixture (edjack post).
- GM A4S-270R: 4-speed, used with M52 engine
- GM A5S-360R: 5-speed, used with M52 engine
- GM A5S-390R: 5-speed, used with M54 engine
- ZF 5HP19: 5-speed, used with M54 engine (gtxragtop thread)
- ZF 5HP24: 5-speed, used with M62 engine
- ZF 5HP30: 5-speed, used with M62 engine
Manual transmissions (Qsilver7 post)
- ZF 5SD-320Z: 5-speed, used with M52 and M54 engine
- Getrag 5SD-250G: 5-speed, used with M54 engine (USA 525i)
- ZF/Getrag S6S 420G: 6-speed, used with M62 engine
Transmission fluid replacement
Despite BMW's claim that the transmission oil is a "lifetime" fluid, it has been found that the oil becomes contaminated over time, and therefore requires replacement. The type of oil needed is indicated by the colour of the label on the transmission sump (MatWiz thread, Bluebee thread, hungdynasty post).
For the ZF 5HP19, several brands offer fluids conforming to the Esso ATF LT 71141 specifications (fudman thread).
Discussion about flushing very old auto transmission fluid: toothless02 thread
GM A4S-270R fluid flush procedure: jvcajita thread
GM A5S-390R fluid flush procedure: Jason5 thread
ZF 5HP24 fluid flush procedure: vicent page
Manual transmission fluid flush procedure: CNN thread
Trans Failsafe Prog
This warning light indicates that the automatic transmission has gone into "limp home" mode, which uses only 3rd gear. Possible causes include: low battery voltage (1, 2, 3), a wet sensor (4) or electrical problems unrelated to the transmission (5). Mechanical failure of the gearbox occurs is less likely, but also a possibility (6, 7).
Torque converter slip
An internal seal within the torque converter can fail, causing a "Excessive torque convertor slip" error code (gtxragtop post).
Tools for M62 clutch replacement: DavidPorter thread
Dual Mass Flywheel (DMF)
The OEM flywheel is a DMF, which is expensive to replace and cannot be resurfaced. Therefore, some people prefer to replace it with an aftermarket single-mass flywheel (1, 2), however there are reports of the replacement flywheel or solid clutch causing causing gearbox chatter in neutral (3, 4, 5).
Clutch Delay Valve (CDV)
Most manual transmission cars (except M5) include a CDV to prevent clutch abuse. However, many people find it hard to drive smoothly with the CDV installed. To disable the CDV, it can either be modified (Zeckhausen) or removed (CN90 thread, BMWtips).
Discussion about diff oil types and brands: Bluebee thread
M57 replacement procedure: philthompson thread
M62 replacement procedure: BlackBMWs thread
For a failed Universal Joint, most people replace the driveshaft, however a DIY replacement of the uni joint is also possible (3).
When disconnecting the driveshaft, beware that the rear of the gearbox can drop (4). Therefore, the gearbox needs to be supported beforehand.
Discussion about oil leaks: dannisieze39 thread
Transmission conversion (auto to manual)
Swapping an E39 from auto to manual is more complicated than older or simpler cars, due to the electronic configuration (coding) work required. However, several people have successfully converted an E39 from automatic to manual (zer0vette thread, Chigga thread,geargrinder thread).
Suspension and Steering
In the front struts, the shock absorber (also known as "damper") forms part of the suspension geometry, unlike the rear suspension. Poor braking and shudder during braking can be caused by failed front shock absorbers (1, 2).
- M52/M54 front suspension overhaul procedure: Bimmer Zeit video, cn90 thread, beisansystems.com
- Discussion about worn shock absorber symptoms and replacement options: Bluebee thread
Rear shock absorbers
Worn out rear shock absorbers can cause noises over bumps, poor ride and poor handling.
Air springs (Touring only)
Touring models with Self Levelling Suspension use air springs in the rear suspension (front suspension is the same as sedans). Cracked rubber can cause the air springs to leak.
There are various aftermarket rear suspension kits for touring models, which either retain the air springs or replace them with coil springs ()
Rear ball joints
Worn out rear swing-arm ball joints can cause vibration, squeaking, poor handling and uneven tire wear. Ball joints on M52/M54 cars can be removed with commonly available tools (), however M62 cars require a special tool to be purchased (, ) or custom made ().
- M52/M54 replacement procedure: MatWiz thread, Bimmer Zeit video
- M62 replacement procedure: cdb3113 thread, Al's540i thread, Edwin post
Steering rack / steering box
The six-cylinder cars use a rack-and-pinion system (aka "steering rack"), while the V8 cars use a recirculating ball system (aka "steering box").
M52/M54 replacement procedure: iDrift thread
M52/M54 rebuild discussion: champaign777 thread
Discussion about causes of heavy steering: boostmaster thread
Thrust arm bushings
A failed thrust arm bushing is a common cause of vibration at 50-60 mph ().
M62 replacement procedure: hotswimmer thread
Front Wheel Bearings
Growling/humming noises from the front wheels are often caused by worn out front wheel bearings.
Video DIY replacement procedure: BIMMERZEIT
Power steering fluid leaks
Power steering fluid leaking from the reservoir or hose can drip into the alternator, possibly causing damage ().
Common sources of leaks are the hose, hose clamp, reservoir cap o-ring and vent hole in the reservoir cap (, ). Some people fill the reservoir cap vent hole with a Q-tip to prevent fluid leaking through the hole (). Often a leak at the top of the hose can be fixed by cutting off a small length of hose at the top and replacing the clamp with a hose clamp ().
Power steering fluid flush
Power steering pump brackets
M62 owners have reported power steering pump mounts spontaneously failing ().
Failure of the power steering pump mount can disable the water pump, so the engine should be shut off quickly, before it overheats.
Rear sway bar
The sway bar (called "stabilizer" in the BMW schematics) reduces body roll in cornering.
M52/M54 replacement procedure: Jackcat559 thread
Wheel alignment affects handling and tyre wear. The BMW alignment specification requires weights to be added to the car during alignment measurements, but some people believe the correct alignment can be obtained without the weights ().
Rear wheel alignment procedure: cn90 thread
Free play in rear suspension
Discussion about worn wheel bearings, bushings, ball joints and tie rods: rdl thread
Brake pad and rotor replacement
Brake pads are a maintenance item and should be replaced before the metallic backing starts scraping on the rotor. If the rotor is uneven, it should be machined to restore the flat and straight surface. However, if the rotor is too thin, it needs to be replaced instead (1). It is recommended that "bedding in" be performed for new brake pads (2).
Discussion about causes of brake shudder: stigst3r thread
To replace the brake fluid without adding air bubbles to the system, the process is called "bleeding" the brakes. The traditional method requires a second person to pump the brake pedal, or equipment is available to "power bleed" without needing a second person. If there are air bubbles in the ABS pump, specialist software is required to bleed the system (1).
Regarding the choice of brake fluid, BMW recommends "low viscosity" DOT4 (2).
ABS failure / trifecta
Early E39 models use Active Stability Control (ASC), while later models use a more advanced version- Dynamic Stability Control (DSC).
If the DSC, ABS and brake warning lights on the dash are all on, it is known as the "trifecta". This commonly caused by failure of the ABS module or a wheel speed sensor. A "brake pressure sensor" error is often present with the trifecta, however it is rare that the fault is caused by the brake pressure sensor (1).
The speedometer takes its input from the left-rear wheel speed sensor (2), which may help determine the fault. If ABS error code 88 is present (which may cause only the DSC warning light), this may be due to the ABS module or ABS pump (3).
In some cases, the ABS module can be repaired (4, 5, 6), however the repair is not always successful- even by professionals (7). If the ABS module is replaced, the steering angle sensor needs to be recalibrated (8).
Replacement procedure for ABS module: BlackBMWs thread
Discussion about companies who repair ABS modules: Larrick thread
Wheel speed sensors
It is reported that a scratch on a wheel bearing can cause the ABS to continuously activate at low speed (1).
Discussion about causes of faults: M00n3ater thread
Brake pressure sensor
Steering angle sensor
Replacing the steering angle sensor or the ABS unit may require steering sensor calibration. This can be done using Tool32 (1) or INPA (2). It is also suggested that the calibration can be done without any tools (3).
Replacement procedure: rdc8118 thread
Parking brake (handbrake)
Overhaul procedure: cnn thread
Once you have identified whether you have the High OBC or Low OBC (1), you can unlock the "secret menu" to obtain information about the vehicle. This menu also allows you to calibrate the fuel consumption readout (2).
Missing pixels on the dash and MID display is often caused by problems with the ribbon cable. Replacement ribbon cables are available and there are DIY instructions (1), however the job is very difficult and there are no reports of successful DIY repairs (2, 3). Therefore, most people have had their MID professionally repaired, or purchased a replacement.
If attempting the repair, the black and white connectors on the ribbon cable are slightly different designs. However, with minor modifications, either colour can be used (3).
MID test mode procedure: RDL post
Volume Two of the Bentley manual contains wiring diagrams.
Trunk wiring harness
Chafing of the wiring harness in the trunk is a common cause of problems with rear lights and can cause other mysterious electrical problems (1).
Lighting Control Module (LCM)
Replacement procedure: mario788 thread
Headlights / rear lights
The dashboard warning lights will come on if the resistance of a light circuit (including the bulb) is not within specification. Some brake light problems have been caused by bulb sockets burning out (1).
Cloudy headlights are a common issue; often the plastic can be restored by polishing (2).
Troubleshooting warning light for rear lights: bmwMobiletech thread
Replacement procedure for centre brake light: bluebee thread
Faults with the stereo (especially aftermarket stereos) can cause the turn signals to stop working (1).
Ignition switch and lock cylinder
Ignition switch rebuild procedure: cal45fan thread
Lock cylinder replacement procedure: SNARF thread
Licence plate light bulb
Replacement procedure: bluebee post
The keys perform 3 functions: immobiliser (EWS), keyless entry (FZV) and alarm (DWA) (1). Cars were originally supplied with four keys: two "master" keys, one "valet" (does not unlock trunk or glovebox) and one small plastic "wallet" for emergency use only (2). Early models use a square shaped master key, later models use a diamond shaped master key. All keys include the EWS transponder required to start the engine.
Replacement master keys from a dealership can be expensive, however aftermarket replacements are also available at lower cost (3, 4, 5, 6). When an aftermarket key is purchased, the EWS module car needs to be reprogrammed (this module can be removed from the car to send to the key supplier). Another cheap solution is to purchase a valet key from the dealership and transplant the EWS transponder into an aftermarket master key (7).
Discussion of options when keys are locked in car: vetaldj thread
Keyless entry (remote central locking)
To unlock a car when the keyless entry is not working, the doors and trunk can be manually unlocked with a key (1). If the car's flat battery prevents the central locking from working, an external battery can be used to power the system (2).
"Initialization" for the keyless entry is required for new keys or when the key battery is replaced (3, 4, 5). Lost or stolen keys can be deactivated so that the keyless entry no longer works for them (6).
Charging key batteries: traviss351 thread
Replacing battery in diamond key: BMW_525i-Noob thread
Replacing rubber buttons in square key: QSilver7 thread
Alarm and EWS (immobiliser)
The alarm is part of the EWS system. Random alarm activation can be caused by a failing battery or hood switch (1, 2, 3). The EWS has 10 "slots" where keys can be programmed, however it is suggested that a new key can be programmed to replace an old key (4).
Siren replacement procedure: BMWtips
EWS overview: bimmerfest pdf
Retrofit procedure: davidf procedure
Carsoft, PA Soft (1), INPA and DIS are commonly used for coding. The following forum contains a lot of information on coding: http://www.bimmerforums.com/forum/forumdisplay.php?233
Door lock actuators are a common failure, causing a single door to be unable to lock or unlock.
A door that is stuck locked is a difficult situation, because the door card cannot be removed while the door is locked. Instead of destroying the door card, a small hole can be made in the door card to access the torx bolt (1).
External door handle
Replacement procedure: TIPenta thread
Trunk lock actuator
A failed trunk lock actuator prevents the trunk (also known as "boot") from closing (1).
Replacement procedure: BMWtips
Trunk strut (sedan only)
- Replacement procedure: cn90 thread
Tailgate (Touring only)
- Discussion about opening a stuck tailgate: bananaman thread
- Replacement procedure for gas struts: xpcgamer thread
Water in rear footwell
Water in trunk
Discussion about clogged drains: HeavyJ thread
Discussion about hood adjustment: JCGinMA thread
Hood release (bonnet release) cable
How to open the hood when the cable is broken: 528inOttawa thread
Splash shield / front undertray
To access the underside of the engine, the splash shield (also known as undertray or "Engine compartment screening- front") needs to be removed. There are a few different designs of E39 splash shields (such as Phillips head bolts vs M10 hex head bolts, and some splash shields have recessed bolt holes).
The splash shield is in two pieces, and the rear section needs to be removed first (1). To remove the front section, remove all the bolts, then slide it towards the back of the car to free it from the front bumper (2).
Upper seal replacement procedure: davegraham page
Door jamb seal discussion: Bluebee thread
Replacement procedure: 540i6.com
Replacement procedure: porksoda thread
The rubber trim cracks over time (1).
Replacement procedure: blackBMWs thread
The OEM headlight adjusters are made from PBT, which over time becomes brittle over time and breaks. This results in the headlights pointing downwards or moving around. There are many options to repair/replace them, such as buying plastic or metal adjusters(1), or making your own adjusters (2). Headlights on 2002+ cars require a different technique for disassembly (3).
The headlight levelling sensor is located in the front suspension (4).
The headlights are not sealed, they have drain tubes (4).
For lubrication of the sunroof guide rails, BMW specifies that an oil should be used (4), such as the oil used on a bicycle chain.
Roundel (BMW trunk and hood badges)
Paint can flake off from the emblem over time. The rear badge is slightly smaller than the front (1).
Rear bumper bar
Removal procedure: pelicanparts.com
Warning: when working around airbags or seat occupancy sensors, disconnect the battery first to avoid triggering the airbag light (1).
These are very fragile, therefore they commonly break. When broken they are unable to be closed.
Cracks may appear in the woodgrain trim over time, especially on the CD player cover (1).
- Interior trim removal procedure: bagman thread
Internal door handle
- Replacement procedure: BMWtips
Cars before 03/99 have a single stage airbag. Cars after 03/99 have a dual stage airbag. Therefore a replacement steering wheel must be in the correct date range for the airbag to function.
If the steering wheel lock jams, it can be unlocked by drilling the underside of the steering column (1).
Takata airbag recall
The airbag for the sports steering wheel on 2002-2003 cars is part of the Takata airbag safety recall.
- Discussion about Takata recall: Blubee thread
Some drivers have found the American front armrest with plastic cradle to be uncomfortable for their elbow, and have replaced it with the European armrest which does not have the cradle. There are several types of European armrest available (1, 2).
Door cards / interior door panels
- Front belt replacement procedure: cn90 thread, e39dream thread
- Front pre-tensioner replacement procedure: cn90 thread
- Front window regulator replacement procedure: MatWiz thread, 82bmw633 thread, jamesdc4 thread, yaofeng post, frankies-bmw.com
- Extra tips for front windows: bluebee thread, G.P.Burdell thread
- Rear window regulator replacement procedure: BMWtips.com
- Discussion about brands of window regulators: bluebee thread
Phantom window opening
Front seat control module
On the front seats, the cables which control the movement of the seat often fall out. This causes the seats to twist (1).
Rear seat removal
For sedans, the seat base is removed by pulling it upwards at the front. The seat back is removed with two bolts in the bottom corners, then lifted upwards to release it from the two mounting tabs at the top (1, 2, 3).
For fold down rear seats, the mounting bolts are slightly different (4- see Figure 28).
For integrated child seats, there may be additional clips to remove (Black5 post).
- Replacement procedure: DavidC post
Airbag warning light
The latch can fail, making the glovebox unable to be opened (1).
- Removal procedure: wilbura thread
- Discussion about faulty cluster lights: Mobius528 thread
- Discussion about removing stalk: 528iAut thread
Rear parcel shelf
To access some rear suspension components, removal of the parcel shelf is required.
Sources of rattles
Final Stage Unit (FSU)
A common cause of erratic climate control behaviour is the FSU, also known as "blower resistor". It has also been known to drain the battery, by running the fan when the car is switched off (1). The FSU can be tested (2, 3). One mode of FSU failure is ageing resin on the circuit board, which can be repaired (4).
On right-hand drive cars, the FSU is on the drivers side, so the kick panel needs to be removed (5).
Some cars also have a rear FSU (6).
- Cabin air filter replacement procedure: bluebee thread, cn90 thread, Bimmer Zeit video
- Discussion about cabin air filter brands: jbalenzano thread, doru thread
Erratic fan behaviour is likely due to a failed Final Stage Unit.
- Diagnosing interior fan problem: VA525FREAK thread
- Procedure for replacing blower motor: E39source video
Evaporator condensation (water on ground/interior)
Condensation from the aircon condenser can cause water to drip below the car (1). This is not the sign of a fault, however make sure not to confuse leaking coolant for water.
If the evaporator drains are faulty, this water may enter the cabin (2).
Ambient Temperature Sensor
This sensor often damaged by parking curbs, due to its location. When the sensor is open circuit, it reads as -40°F (-40°C); however a faulty sensor can also read high.
Automated Recirculated Air (AUC) mode
When the climate control recirculation mode is set to auto ("A"), the AUC sensor is used to determine whether fresh or recirculated air is used (1).
It is common for this vent to crack in the top-left corner (1).
- Replacement procedure: porksoda thread
It is common for the climate control temperature adjustment buttons to crack.
- Repair procedure: violinARC
A single beep is a warning that ice is likely, due to the outdoor temperature. A triple beep is the hourly alarm (1).
Milage tamper dot
A dot in the dash display indicates an error with the mileage calculation (1), therefore the mileage data may have been tampered with.
A faulty or loose compressor can cause rattling sounds from the engine bay (1).
Heater control valve
Climate control units on cars manufactured after 09/2000 use a solar sensor. The climate control will work without the solar sensor, however it will cause a fault code (1).
CD changer "no discs"
AM radio reception
- Repair procedure: cnn thread
For cars built after 09/2002 without navigation, the BMW aux cable can be retrofitted (1, 2, 3). For earlier cars, retrofitting of the BMW aux cable also requires stereo to be replaced with one from after 09/2002 without navigation (4).
Other options for listening to audio from mp3 players etc include tape to aux cable adaptors, FM transmitters and aftermarket stereo replacements.
BMW recommends jump starting be done using the positive connection on the intake manifold and the earth connection on the strut top (1). Before attempting to start the dead car, it has been suggested to have the cars connected with the donor engine running for 3-5 minutes (2).
- Discussion about jump starting: Ustad thread
Technical Information System (TIS)
The official BMW information provided to dealerships. It contains repair procedures and other technical information.
Raising/jacking the car
The jack pad near each wheel is the preferred location for jack stands (1). However, finding a lifting location is not as straightforward.
For the rear of the car, many people use the differential, although others believe this can damage the differential or bushings (2).
For the front of the car, there is a jacking point on the engine crossmember (3- see second photo), however this location is hard to access on some models (eg requiring a long-reach floor jack) and some people have reported that the jacking point is not fitted to their cars crossmember. An alternative is to lift the car on each side using the chassis rails (4- see Figure 6), which requires removal of the plastic underbody shields on each side of the car.
Instead of using jacks, another method of raising the car is with ramps (5).
Jack pads (wind noise)
Diagnosing windshield wiper problems: 540isaac thread
Windshield washer and headlight washer
Some E39s have the "intensive wash" option, which uses a separate reservoir and pump. The Touring models include a washer for the rear window.
Leaks from the reservoirs can be caused by the grommet (shabbaman thread). Problems with the hoses can cause a water leak and reduced effectiveness of the washer jets. Blocked jets can cause reduced effectiveness.
- Discussion about windshield washer pumps: mimic thread
- Discussion about intensive wash and Touring rear window wash: Kel thread
- Washer jet adjustment procedure: FIA thread
- Reservoir leak repair procedure: cn90 thread, Jamaican71 thread
- Hose replacement procedure: jamesdc4 thread
Parking Distance Control (PDC)
Front and rear acoustic parking sensors were available on the E39. The kit was also sold as a retrofit (1).
- Discussion about PDC faults: Mfive41 thread, PliSsk thread, Wiggi post
- Replacement procedure: Edwin post
Wheels and tires
- Wheel fitment specifications: iceman4169 thread
Tire Pressure Monitoring System (RDC / TPMS)
An option on euro-spec E39s (1)
Replacing a broken engine
The E39's large amount of integration between the electronics of the engine and the rest of the car ("body electronics") means that replacing engines is more complicated than on older cars.
Also, the immobiliser system (EWS- described here) requires the several components to be synchronised. Some of these components are unable to be re-programmed or reprogramming requires expensive equipment. The components which need to be synchronised are: DME, EWS control unit and the electronic chip inside the ignition key. The easiest method to maintain synchonisation is to send the new DME, EWS and the car key to a specialist for re-coding (MichaelK5990 thread, 766jack thread). Having the existing key re-coded avoids the need to replace all the locks in the car. Another option is use the DME from your old engine on your new engine.
Even matched EWS components can need re-syncing (HTK12 post).
Replacement with identical engine:
Using a replacement engine of the exact same specification (same family, same capacity, same vanos configuration) enables the old engine's electronics to be used with the new engine (1). This avoids the complications involved with modifying the EWS system.
Alternative sources for replacement engines:
- M52: E36, E38 (pre September 1998 only) or Z3 (pre September 1998) (1)
- M52TU: E46, E38 (post September 1998 only), Z3 (post September 1998)
- M54: E46, Z3 (3.0L only), Z4 (pre September 2006), E53. Note: the E60 and E83 models also used the M54 engine, however they started production after the E39 was discontinued, therefore there may be changes which are incompatible with the E39
- M62: E38 (pre September 1998 only), E31 (4.4L only)
- M62TU: E38 (post September 1998 only), E53 (pre July 2003 only)
Note that coding is required when installing an engine from an automatic car into a manual car, and potentially vice-versa.
Replacement with same engine family, but different engine specification:
This section described engine swaps within the same family (eg M52, M54, M60 or M62). Although the M52 and M54 engines are similar in many ways (similarly, the M60 has many similarities with the M62), unfortunately the small differences may cause difficulties for an engine conversion (1). Therefore, it is often much more straightforward to use a replacement engine from the same family. Nonetheless, there are still challenges when remaining in the same engine family. Therefore, in addition to the issues noted above, the following issues should be considered.
Capacity changes require a change of engine tuning to operate at its full potential. It is possible to get the new tune coded into your old DME (2), thus avoiding EWS modifications. Also, it may be possible to 'virginize' a DME so that a new tune can be used (3). Note that sometimes the ancilleries are different for each engine capacity, for example the maf, intake, airbox are different between the M54B25 and M54B30 (4).
Changing the vanos configuration (eg replacing a single vanos M62 engine with a dual vanos M62TU engine) is considered not a practical option (1, 2, 3), since it would require extensive modification to the cars electronics.
Engine swaps for power increase
"Anything is possible, the question is if it is worth your time and money. I have seen someone swap an engine out of a 2006 M3 into a 1989 M3. Was it really cool and fast? Yes. Was it really worth spending almost $20k for it? No. For that kind of money he could have built up an impressive euro S50 and blown away his current setup" -Jimmys530i
The issues discussed above in replacing a broken engine all apply, plus added complications due to differences in how the car is configured for each engine.
E39 engines- 6 cyl:
- BMW M52TU replacement of M52: discussion thread, discussion thread
- BMW M54 replacement of M52: Gary@GAS build thread
- BMW M54 replacement of M52TU: raymond3080 build thread (note that this build retrofitted the M52TU intake onto the M54 engine), flashmeow build thread (similarly, this build used the M52TU DME on the M54 engine),Irogers80 build thread, discussion thread, discussion thread. As some of the above builds show, the M54 engine can run on an M52TU DME, which avoids many of the electronic complications. However, the M54 engine will not be running optimally in this state.
- BMW M52 replacement of M54: rmb213 discussion thread
- BMW M52TU replacement of M54: discussion thread
E39 engines- V8:
- BMW M62TU replacement of M62: Theoretically, this swap is similar to M54 replacement of M52TU (see above).
- BMW S62: This swap is expected to be very difficult (1, 2)
- Chevrolet LS1: rao thread, Mutty build thread, RVAE34 build thread, Stutts115 build thread, M5_Hunter build thread. The LS1 is probably the most popular swap involving a non-BMW engine.
- other Chevrolet V8 engines: nsogiba LQ9 thread, James39 LQ4 thread
- Nissan RB26: Mda185 post
- Toyota 2JZ: bmw_2jz thread, Mr535i build thread, Oz923 thread, 930chas build thread