O2 Sensor Question - is 700-800 mV at idle normal? . . . chasing 20% drop in mpg - Bimmerfest - BMW Forums



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  #1  
Old 02-25-2017, 12:16 PM
RPsX5d RPsX5d is offline
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O2 Sensor Question - is 700-800 mV at idle normal? . . . chasing 20% drop in mpg

My X5d - 2011MY, June 2010 build, ~112,000 miles . . . O2 sensor was last replaced 5 years/~78,000 miles ago,

Trying to eliminate weak O2 sensor as the cause for a 20% drop in fuel mileage.

There are no CEL/MILs . . . trying to determine if O2 sensor is weak, but not weak enough to trip a fault code.

After coolant has reached 87/88C, at idle (~700 rpm), O2 sensor voltage is 700-800 millivolts.

Normal highway cruising, no incline, steady 75 mph it is 450-500 millivolts.

Going downhill on the highway (or taking the leg off the throttle) voltage jumps to 1200 millivolts - either engine is running VERY rich or O2 sensor not functioning properly. (I thought max for O2 sensor was 900 mV).

Moderate to hard acceleration (~3,000+ rpm), O2 voltage drops to ~300 mV . . . engine running lean.

Given I am using a Bluetooth dongle for the OBD reader, there might be a slight lag between actual engine output and display on the smartphone.

Does 450-500 mV at highway cruising, 700-800 mV idling and ~1200 mV at zero-load (engine braking) look right?

Thanks.

PS: Currently using BlueDriver OBD2 reader . . . Carly on the way, will cross check to make sure OBD2 reader is accurate/not the issue.

Last edited by RPsX5d; 03-13-2017 at 12:00 PM.
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  #2  
Old 02-27-2017, 02:52 PM
lpcapital lpcapital is offline
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I do believe that what the X5 mounts is a wideband O2 sensor not a narrowband. While a narrow band basically tells you whether you're running stioch, lean or rich without being able to measure AFR, wideband measure AFR.

Generally (and simplified) the way a wideband is as follows. You have a narrowband sensor contacting the exhasut gases (gasses are drawn in a chamber where the zirconia does its magic) and an oxygen pump that uses current to pump O2 from the outside to the chamber or viceversa. The amount of O2 transported is proportional to the current drawn by the pump and, as said can go both directions. The way that AFR is calculated is based on the amount of O2 (or current) needed to be added or subtracted (you flow current one way or the other, i.e. change polarity, negative volts) to the gas stream to get the narrowband to read stoich.

I'll admit I've not checked the X5, but that would explain the apparently odd readings. Are you sure it shows millivolts and not milliamps? The latter is normally the output (or input actually) of a wideband.

Interesting is the NOx sensor works similarly: it does not measure NOx directly, but you have a catalist element (similar to the LNT) that split the NOx and then a zirconia element that measures the amount of oxygen released...
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Old 02-27-2017, 11:31 PM
RPsX5d RPsX5d is offline
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Thanks.

Yes, it reads volts (not amps) . . . I just got my Carly PRO set up yesterday . . . both Carly and my previous OBD reader (BlueDriver) read volts.

Yes this X5d uses the heated wideband O2 sensor with 5 wires (P/N 13627801158, #13)

Here is a bit more info about this particular Bosch O2 sensor.

Page 135 of the Diesel Technology PDF (attached) indicates this O2 sensor is a Bosch LSU4.9 broadband oxygen sensor.

Elsewhere I read the pump cell signal is in amps (-9mA, rich to 18mA, lean), but the measurement cell signal is in volts - stoic is ~450 mV.

Cruising at a steady 75 mph on a highway with no inclines (up or down), my O2 outputs almost exactly 450 mV - both Carly and BlueDriver indicated the same value.

When I step on the throttle, O2 reads ~300 mV (lean) . . . and when I let go of the throttle, O2 jumps to 1.2V (very rich).

**Assuming** O2 sensor is working properly, then every time I let go of the throttle, the engine is running very rich - and that probably explains my original issue - a 20% drop in fuel mileage.

Interestingly, at idle, O2 shows a steady 700 mV . . . not the 1.2V when I abruptly let go of the throttle.

Given there are no CEL/MIL, not sure if I can assume O2 sensor is good. Thoughts/comments?

Still figuring out Carly . . . but BlueDriver OBD reader showed the EGR-Low valve (EPDW) almost always closed and the EGR-High valve (electrical, not vacuum) always wide open. Don't know if this is normal operation for these two EGR valves . . . somehow the EGR-Low remaining shut most of the time doesn't seem correct . . .
Attached Files
File Type: pdf BMW Diesel Technology May2012 PAGE-135.pdf (53.1 KB, 56 views)

Last edited by RPsX5d; 02-28-2017 at 10:09 AM. Reason: Forgot to attach PDF
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  #4  
Old 02-28-2017, 12:36 PM
lpcapital lpcapital is offline
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Perhaps you know this, but in general you need to be careful in interpreting O2 readings from a diesel engine with emission control systems similarly as you would in a gasoline car. In a gasoline engine the concentration of O2 in the incoming air is the same whether you're running part throttle, full throttle, under loar, no load, idle. The air that gets in is always the same fresh air from the atmosphere. In today's emission controlled diesel is not quite that: the EGR is there the reduce oxygen concentration in the incoming "air". As a result the O2 reading in the exhaust stream is not only a function of the fuel injected, but is also a function of the EGR rate.

And monitoring EGR rate is one of the primary roles of the wideband sensor in the exhaust. Diesel use a closeloop of MAF to measure incoming fresh air, MAP to measure the air+EGR entering the cylinder and wideband O2 to dial in EGR rate.

In your specific situation the "rich" condition may not be a high AFR due to high fueling, but high AFR due to high EGR rate.

I haven't been driving nor monitored the X5 so I can't speak directly but I have a CS2 monitoring on the Ram. One thing I noticed that scared me at the beginning is that coasting downhill my intake air temperature would skyroket to 260F. Then I realized that the reason is that while coasting the engine activates the throttle plate, and cranks up the EGR. The IAT probe is right next to the EGR inlet explaining the high temperature. I would guess the result would be a super rich condition in the exhaust because the engine is basically sucking in exhaust (that by definition has less O2 that fresh air) which is then fueled up just a bit and what comes out the other end has practically no O2 left. This strategy I believe is in part to maintain NOx down (coasting downhil would be a super lean condition) and sustain EGT so the exhaust components wouldn't cool down too much and get out of efficiency range. I noticed after deleting that in the same stretch of road my EGT drop as low as 200F which would basically deactivate any chemical reaction occurring in the exhaust.
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Old 03-02-2017, 07:27 PM
RPsX5d RPsX5d is offline
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Thanks for the response . . .

My **guess** this is not an O2 sensor issue - why - the mV output works like clockwork - at cruising it is ~500 mV, mild/hard acceleration - ~300 mV, coasting - 1.2 V and idling - 700 mV. These figures are very consistent.

Unlike the O2 sensor, the EGR-L (an EPDW variable valve) almost never switches on (0%) and when it does (for no obvious reason or pattern), values are all over the place - sometimes 60%, other times much less.

The EGR-H (an electrical, not EPDW, on/off (not variable) valve) is always stuck wide open (95%) . . . the only time I saw it move down from 95% is under hard acceleration (3,000+ rpm).

The only reference material I was able to locate for the EGR-H/L valve functioning is attached - it does not show the amount (%) the valve is open for a given rpm and engine load - shows only when the valves are active, not the %.

A week ago I got the Carly OBD2 Gen2 reader and the Carly PRO app, still getting used to it!

Did a scan and found the dreaded 4D16 NOx efficiency fault code! The interesting part - it did not trip a MIL . . . maybe it has to happen a certain number of times before MIL gets tripped.

I also got a 4B91 fault code for oxidation catalyst and a few other fault codes . . . did the obvious thing, cleared them all, charged the battery (7 year-old) overnight, re-ran the scan and no faults found. So for now in a watch-and-see mode . . . I still have about 8,000 miles before the extended warranty runs out.

For those thinking about Carly, attaching the Fault Report and Freeze Frame Report for the above two fault codes - 4D16 and 4B91. The latter gives a lot of information . . . I am still very new at this, so still digesting this info!

Finally, I still haven't figured out how to get Carly to monitor the two EGR valves . . . I am near certain Carly can do it, my old BlueDriver one did. I want to cross check what BlueDriver showed - EGR-H is open nearly all the time and EGR-L is closed most of the time.

Carly has a bug - the parameter names (at least for the iOS version) does not wrap - so long parameter names get chopped off and very hard to tell which one is which!

Quote:
Originally Posted by lpcapital View Post
. . . you need to be careful in interpreting O2 readings from a diesel engine . . . EGR is there to reduce the oxygen concentration in the incoming "air". As a result, the O2 reading in the exhaust stream is not only a function of the fuel injected but is also a function of the EGR rate.

And monitoring EGR rate is one of the primary roles of the wideband sensor in the exhaust. Diesel uses a closed loop of MAF to measure incoming fresh air, MAP to measure the air+EGR entering the cylinder and wideband O2 to dial in EGR rate.

In your specific situation the "rich" condition may not be a high AFR due to high fueling, but high AFR due to high EGR rate. . . . .
Attached Files
File Type: pdf Carly - Fault Report - 17FEB2017.pdf (215.5 KB, 279 views)
File Type: pdf Carly - Freeze Frame Report - 17FEB2017.pdf (201.0 KB, 162 views)
File Type: pdf BMW X5 - EGR Control Map.pdf (63.8 KB, 50 views)
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Old 03-02-2017, 08:05 PM
FredoinSF FredoinSF is offline
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Carly has funkiness to it. You need to think like a German software engineers over the years and I think you need to think the way they do and then it makes perfect sense. Not...

Anyway, was looking at you reports and something caught my eye on the second attachment:
Found Faults:
--Engine / Motor--
*** 4D16eNOx system efficiency efficiency at low ***
Fault-Set 1 - ( 178448 km)

vehicle speed: 177.00 km/h

The measured from LSU lambda value 0: 46.84 -
vehicle speed: 162.00 km/h
Weighted average temperature of the SCR catalyst (1 byte): -45.88 degC

Do you have over >115k miles and did error come up at >110MPH?
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Old 03-05-2017, 10:42 AM
RPsX5d RPsX5d is offline
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Thanks for the response, sorry for the delay in responding . . . got sidetracked into upgrading the WiFi at the house . . .

German software engineers . . . still shaking my head . . . even basic stuff like monitoring various engine parameters takes so many clicks/touches . . . what takes BlueDriver a single touch is five on Carly!

The extra long parameter label does not wrap down to a second line (see attached screen shot) . . . might be an iOS bug . . .

For me - I am still searching for the PID that will display high-pressure EGR valve position (an electrically, not vacuum, operated valve) and the low-pressure EGR valve position (this one is an EPDW)

If anyone has a workaround for this label not wrapping issue, please post the solution. Thanks!

The distance marker, 178,448 km (or 110,883 miles) is correct . . . I am currently getting close to 112,000 miles.

Vehicle speed, 162 kmph or 101 mph - not impossible, but very unlikely . . . occasionally when I gun it to get out of bunched up freeway traffic I have hit 90+ mph . . . but I don't think I have ever hit 100 mph on this car.

I will pick vehicle speed as a parameter to monitor on Carly and see if it matches up with the speedometer.

PS: Completely unrelated . . . finally installed Google mesh WiFi (3-pack version) . . . got tired with multiple SSIDs to eliminate dead spots . . . Google mesh does exactly what they claimed it would . . . handoff to different pucks works like clockwork (tested it by walking around the house and checking the BSSIDs using the Network Analyzer app) . . . with Google WiFI, one of the rooms jumped from 7 Mbps to ~400 Mbps! I have ATT GiggaPower . . . wired connections run at ~900 Mbps up/down . . . wireless, pretty much everywhere in the house is ~400 Mbps . . . solved dead spot issues once and for all!

Quote:
Originally Posted by FredoinSF View Post
Carly has funkiness to it. You need to think like a German software engineers over the years and I think you need to think the way they do and then it makes perfect sense. Not...

Anyway, was looking at you reports . . . and something caught my eye on the second attachment:
Found Faults:
--Engine / Motor--
*** 4D16eNOx system efficiency efficiency at low ***
Fault-Set 1 - ( 178448 km)

vehicle speed: 177.00 km/h

The measured from LSU lambda value 0: 46.84 -
vehicle speed: 162.00 km/h
Weighted average temperature of the SCR catalyst (1 byte): -45.88 degC

Do you have over >115k miles and did error come up at >110MPH?
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  #8  
Old 03-05-2017, 12:44 PM
ingenieur ingenieur is offline
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Quote:
Originally Posted by lpcapital View Post
Perhaps you know this, but in general you need to be careful in interpreting O2 readings from a diesel engine with emission control systems similarly as you would in a gasoline car. In a gasoline engine the concentration of O2 in the incoming air is the same whether you're running part throttle, full throttle, under loar, no load, idle. The air that gets in is always the same fresh air from the atmosphere. In today's emission controlled diesel is not quite that: the EGR is there the reduce oxygen concentration in the incoming "air". As a result the O2 reading in the exhaust stream is not only a function of the fuel injected, but is also a function of the EGR rate.

And monitoring EGR rate is one of the primary roles of the wideband sensor in the exhaust. Diesel use a closed loop of MAF to measure incoming fresh air, MAP to measure the air+EGR entering the cylinder and wideband O2 to dial in EGR rate.
+1 ^
This is a very good functional description. During decel the diesel engine has no fuel being injected in a normal operating mode - so it is essentially only pumping air.

Very small mg/stroke pre-injections continue if precondition are met for ongoing zero-mass adaptation.

It is important to maintain combustion chamber temperatures though. If no combustion is occurring then exhaust temperatures drop quickly.

Unlike a petrol engine - fuel injection rates are not 'trimmed' in a diesel.

Lambda response, charge-air temp, ambient temp, ambient pressure, exhaust pressure before turbocharger, and measured air-mass to the greatest degree determine the necessary EGR rates.

Diesels get all the air they want - as lpcapital stated - EGR just dilutes O2 content - this is necessary to control combustion temperatures keeping smoke and NOx emissions in check. All of this is modeled in the calibration with some small adaptations needed to adjust for component aging.

The results from CARLY are useless IMO - various implausible temperatures besides the vehicle speed deviation are incorrect.

A proper logging tool is necessary for fast and accurate sampling of DDE data other than scan tool PIDs.

Check out the following links:
http://www.bimmerforums.com/forum/sh...ime-graph-view

The E90 diesel guys are active with it.
http://www.e90post.com/forums/showthread.php?t=1079838

Last edited by ingenieur; 03-05-2017 at 12:55 PM.
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Old 03-05-2017, 05:44 PM
RPsX5d RPsX5d is offline
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Thanks folks for your very detailed explanations . . . my understanding of how all of this ties together has certainly increased, to say the least!

I completely agree with you OBD scanners have their limitations . . . Carly is somewhat dodgy (I got it mainly to get a bit more BMW specific fault codes versus what I had) . . . a proper diagnostic tool is what is needed here - something like the Rheingold or the TestO.

As noted elsewhere, I have a practical issue . . . gave up my laptop (donated it to a more needy person) for a powerful desktop and iPad Pro for travel needs . . . so now I have no way to run Rheingold or TestO . . . maybe I should have held on to that laptop . . . oh well . . .

The other point, since there are no CELs, I am constantly watching various parameters whenever I drive the car . . . OBD scanners are quite convenient for such use . . . hooking up a laptop everytime I take the car out can get tedious . . .

All that said, I am still trying to figure out what a "normal" low and high pressure EGR injection should look like. I understand it depends on many things . . . but I am only trying to figure out whether the low-pressure staying at 0% commanded EGR most of the time is normal . . . somehow that doesn't seem right . . . I was even told the EPDWs are known to have issues.

I am half tempted to swap out the low-pressure EGR EPDW as part of "routine maintenance" . . . would definitely do it if I knew 0% commanded EGR is not the norm.

Yes, I plan to get my Indy to check out all the vacuum hoses when I am there next . . .

Again thanks for all the suggestion/information . . . I will definitely report back on the progress I make.
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Old 03-06-2017, 10:24 PM
RPsX5d RPsX5d is offline
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An Interesting Observation - still figuring out what it is indicatiing

A brief summary for those coming directly to this post . . .

Initial issue - a 20% drop in fuel mileage (now at 18.3 mpg) . . . BlueDriver (OBD reader) showed the low-pressure EGR is staying off (0%) most of the time, high-pressure EGR stayed open most of the time (~95%), coolant temp steady at 86/88 C, O2 sensor "appears" to be functioning fine . . . most important - no CEL/MILs . . . to me, a 20% drop in mpg is saying something . . . CEL will trip eventually . . . 8,000 miles left in the extended warranty.

A few days back I got my Carly . . . did a scan, found two fault codes - 4D16 (DeNOx system efficiency low) and 4B91 (oxidation catalyst / HC conversion too low during the exothermic reaction). Cleared them both, overnight charged the 7-year-old battery and they have not returned since . . . zero fault codes now.

Since I have yet to figure out how to monitor low & high-pressure EGR valve using Carly, I went back to BlueDriver.

Interesting find - high-pressure EGR valve (an electrical, not vacuum controlled valve) "appears" to be functioning fine . . . prior to clearing the fault codes (4D16 & 4B91) EGR-H was stuck at 94% . . . now under uphill/acceleration, EGR-high drops off (moves towards 0%), highway cruising, it is around 50-60%, sometimes goes as high as 90%.

As others here have indicated, the exhaust gas is used as a way to dilute the O2 content of the incoming air . . . EGR-H is acting as expected - under acceleration or uphill climb, more O2 is needed, and EGR-H is backing off - this makes sense.

This time around, I am monitoring commanded EGR, actual EGR and EGR error for both EGR-H and EGR-L.

Commanded and actual EGR-H are tracking beautifully with the EGR-H error showing 0% most of the time. The EGR-H valve is an electrically controlled valve, not vacuum controlled.

EGR-L - all three parameters (commanded, actual and error) remain at 0% most of the time. Not sure if there is an rpm minimum before EGR-L kicks in. Every so often, for no obvious reason, while cruising the highway, EGR-L kicks in . . . actual % tracks commanded % quite well, error is close to 0% . . . then all of a sudden it EGR-L shuts off - almost feels like a loose contact if this were an electrically operated valve. EGR-L valve is an EPDW, and some have pointed out, these EPDW valves are known to have issues.

When EGR-L shuts off, EGR-L error shoots up to 99% . . . I thought EGR error is a computed value, so not sure why it is reading 99% when commanded and actual are both at 0%. No, it is not a case of the software didn't update the EGR-L error field . . . just prior to commanded and actual EGR-L dropping to zero, the error is a low number (~10%), then commanded and actual EGR-L drops to zero and error shoots up to 99%.

Another observation - when EGR-L kicks in, EGR-H decreases . . . and when EGR-L shuts off, EGR-H increases . . . almost like DDE is using EGR-H to compensate for reduced EGR-L function.

My understanding, I may be wrong here - EGR-L is better at O2 dilution and temperature control - unlike EGR-H, EGR-L is tapped much further downstream than EGR-H (cooler exhaust gas), EGR-L is introduced upstream to both the turbochargers and intercooler . . . so my expectation was EGR-L will be operating most of the time and EGR-H kicks in as-and-when needed.

I am still searching for info on the parameter ranges for EGR control - things like engine rpm, engine load, coolant temp, etc etc. Once I find it, some of these observations might make more sense.

As always any thoughts/ideas that crossed mind are always welcome! Thanks.
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Old 03-09-2017, 11:20 AM
RPsX5d RPsX5d is offline
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Fair warning - this may be a dumb question!

I have a good understanding of the old style diesel engine - mechanical governors to control speed, etc.

Modern diesel engines, to manage emissions, etc . . . uses EGR to control (or dilute as Ipcapital phrased it) the amount of O2 entering the combustion chamber.

A bunch of sensors reports back to the DDE various parameters - charge air pressure, various temperature sensors (intake, charge air, coolant, exhaust, ambient, etc etc), throttle position, vehicle speed, etc etc. The DDE takes all this into account and determines an optimum amount of EGR (commanded) . . . and the two EGR actuators (high and low-pressure) then carry out the command, which is monitored as EGR actual.

Based on the amount of EGR introduced, or the O2 level in the combustion chamber, the amount of diesel injected is varied. i.e. the amount of diesel injected is not a constant, it varies, among other things, according to the amount of EGR injected, and the amount of EGR injected depends on the values the sensors (listed above) reported back.

Is my understanding correct?
i.e. in a mathematical formula sense - the amount of diesel injected is the *dependant* variable and the variables like the charge air temp, throttle position, vehicle speed, etc etc are the *independent* variable. True?

Here is where I am going with this line of reasoning . . . given my EGR-L is closed most of the time (opens in an erratic manner), the engine is constantly getting less EGR than it would have with a properly functioning EGR-L valve . . . less EGR means more O2 in the combustion chamber than required . . . assuming, diesel amount to be injected is based on, among other things, commanded EGR - diesel injected will be insufficient for the amount of O2 *actually* present . . . leading to higher O2 content in the exhaust . . . which then loops back and asks for more diesel to be injected . . . vicious cycle . . . ultimately ending up in more than necessary diesel getting injected than otherwise if the EGR-L valve was functioning properly . . . explains the drop in mpg.

Sherlock Holmes??? . . . could be the detective who went after OJ!

PS: I am still searching for a rough description of EGR-L valve operation when it is working properly . . . like - approximate X% while idling, low-speed city run, highway run etc. etc.
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Old 03-14-2017, 09:51 AM
RPsX5d RPsX5d is offline
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Update . . .

After the weather warmed up in the Bay Area, low-pressure EGR valve started to work . . . here is the pattern now . . .
  • morning starts, initially both EGR-H and EGR-L are at 0%, as the car warms up EGR-H starts to kick in, EGR-L continues to remain at 0%
  • AFTER the car has reached near normal operating temp, both EGR-H&L kicks . . . the amount varies, sometimes High is more, other times Low is more . . . assumed this to be normal . . . EGR amount is dependent on a whole host of input parameters . . .
  • Idling at a traffic light, EGR-L completely cuts out (0%)
  • Uphill, hard acceleration, etc (basically increased engine load) . . . both EGR valves drop to 0%
All this "appears" to make sense . . . most likely with the weather warming up, some loose contact is now making good contact . . . would be nice if we got another spell of really cold weather to see if EGR-L will remain stuck at 0% or come on/off erratically . . .

There is a 4D16 fault code stored in the DDE . . . my *guess* one or both NOx sensor is borderline out . . .

Still waiting for the amber colored 999 iDrive message . . . 12,000+ miles since dealer topped off both DEF tanks. Plan is to add 2.5 gallons to passive tank and let the system transfer the 3 liters or so to the active tank. If all of that goes well, it is confirmation DEF transfer is working fine.

4D16, based on what I read, could also be due to a clogged or partially clogged DEF injector . . . not sure how to differentiate clogged DEF injector versus bad NOx sensor . . .
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Old 04-05-2017, 08:24 AM
NickTheStick NickTheStick is offline
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Subscribing for updates.

Having a similar issue with my 12' X5D. Currently at 51k miles. Always dealer serviced, and have extended maintenance through 2018 (oil changes, brakes, fuel filter etc.)

Dealer just recently replaced the fuel filter. Noticed a ~20% drop in mpg. Vehicle sees 50/50 city/highway driving.

Just ran a diagnostic via carly. Idle coolant temp is 181.4F, which is acceptable. Everything I have read thus far points to a faulty thermostat as the culprit for low MPG.

What also interesting is that I have a ghost code for 4D16. First time I've seen this. Looks like its been there for about 700 miles, which is around the time I had the fuel filter replaced. Wonder if there is any connection?

Maybe I should give BlueDriver a try? Im going to clear the code and see if it comes back.

Freeze frame from Carly:

Found Faults:
--Engine / Motor--
*** 4D16eNOx system efficiency efficiency at low ***
Fault-Set 1 - ( 50196 mi)

Activation period for the main injection 1: 158.92 us
Actuator voltage Up-level (1 byte) 0: 144.00 V
Averaged value of the last three stored values ***8203;***8203;self-diagnosis by the NOx sensor upstream of the SCR: -250.00 %
Charge air temperature after intercooler: 205.00 degC
Current status generator (ISG): 55968.00 -
Detection type (BSD, LIN, SGR): 46.00 -
Differential pressure across the particulate filter: 8.95 psi
DSMEnv_stECUEnv: 52.00 -
dynamically adapted total target exhaust gas recirculation rate in the engine: 80.81 -
Excitation current (ISG): 19.59 A
Exhaust gas temperature before catalytic converter: 40.59 degC
generator power: 212.00 A
Injection amount PoI2 before correcting the fault monitoring: -91.16 mg
MoCSOP_ctErrMM_mp 3: 122.00 -
Pump pressure of the SCR system: 5.46 psi
Pump pressure of the SCR system: 5.86 psi
Rail pressure - Setpoint: 8304.12 psi
Sensorrohspannung the temperature sensor of the urea-water solution: 19.61 mV
Setpoint Load Response Time Generator: 2.20 s
Shut-down time in minutes: 2056.00 min
Speed ***8203;***8203;of the E-fan: 4687.63 rpm
status DSC: 43.00 -
Temperature of the urea-water solution: 478.52 degC
vehicle speed: 101.28 mph
Attached Files
File Type: pdf FaultReport_CarlyForBMW.pdf (19.6 KB, 168 views)
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  #14  
Old 04-05-2017, 03:26 PM
AU Pete AU Pete is offline
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Location: Sydney
 
Join Date: Jul 2015
Posts: 168
Mein Auto: 2007 X5 E70 3.0d
Quote:
Originally Posted by RPsX5d View Post
If anyone has a workaround for this label not wrapping issue, please post the solution.
You can try reducing the font size in your phone settings. This won't make the parameters wrap, but it will fit more characters per line in Carly. Phone settings > Display & Brightness > Text Size.

Possibly a better idea though is to forget looking at the app while you're driving, and just email yourself a file of logged parameters.

Load up to 6 parameters at a time in Carly, then press 'start monitoring', then 'start logging'. Then go for a drive. You may want to have you phone plugged in to a charger to keep it open/charged for a long drive.

When finished, tap 'stop logging' / 'stop monitoring', then go back to the home screen of Carly and go into (from memory) Settings > Send Engine Parameters. Then in the screen that pops up, change the email recipient from the Carly App team to yourself, and hit send. This will send an email with your recent log of params attached as a .txt file.

Note: The email won't send until you have disconnected from the Carly adapter wifi network, and reconnected to your regular home wifi or cellular network.

Once you have the .txt file you can import it into your spreadsheet app of choice - excel/google sheets/numbers etc, and view the complete log of parameters. From there you can graph the results and you may find you can more quickly spot problems as correlations/patterns in parameters will jump out at you.

hth, Pete
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  #15  
Old 04-07-2017, 12:19 AM
serge1's Avatar
serge1 serge1 is offline
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Location: seattle
 
Join Date: Jan 2012
Posts: 1,214
Mein Auto: 2011 BMW X5 35D
Quote:
Originally Posted by RPsX5d View Post
I completely agree with you OBD scanners have their limitations . . . Carly is somewhat dodgy (I got it mainly to get a bit more BMW specific fault codes versus what I had) . . . a proper diagnostic tool is what is needed here - something like the Rheingold or the TestO.
I haven't found a way in Rheingold to get information from different components at the same time like I hear people are getting with Carly.
Graphs are certainly not available in Rheingold.

Which is why I was thinking to get Carly.
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  #16  
Old 04-18-2017, 08:45 PM
RPsX5d RPsX5d is offline
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Location: Bay Area California
 
Join Date: Nov 2010
Posts: 1,240
Mein Auto: X5 35d, MY2011 150,000 mi
Sorry I forgot to post an update sooner . . . thanks, you are exactly right - reducing the font size in the iPhone setting will solve this issue.

New issue - I still haven't figured out how (or if) to get Carly to monitor the EGR valves . . . my previous OBD reader (BlueDriver) used to do this for both high and low pressure EGR valves . . . and yes both commanded and actual values.

I actually watch the phone if road condition allows it . . . it is much easier to get a feel for how the parameters change when you look at it live (versus graphing it later) . . . if necessary, you can graph the interesting parts later.

I mount the phone along the bottom edge of the windscreen by the driver side A-pillar . . . Ram Mounts, although a bit pricey, holds the phone VERY securely and there is zero shaking.

Quote:
Originally Posted by AU Pete View Post
You can try reducing the font size in your phone settings. This won't make the parameters wrap, but it will fit more characters per line in Carly. Phone settings > Display & Brightness > Text Size.

Possibly a better idea though is to forget looking at the app while you're driving, and just email yourself a file of logged parameters. . . .
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  #17  
Old 04-18-2017, 10:01 PM
RPsX5d RPsX5d is offline
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Location: Bay Area California
 
Join Date: Nov 2010
Posts: 1,240
Mein Auto: X5 35d, MY2011 150,000 mi
Very interesting!

I have the same exact issues - 20% drop in mpg and I also have the 4D16 code that has NOT tripped the CEL yet.

My X5d - June 2010 build, MY2011, ~113,000 miles.

No I don't think the thermostat is the issue here . . . your 83C is plenty good, I would only start looking at the thermostat if it dips below 80C, even then I doubt it will have such a dramatic effect on mpg. My thermostat holds it around 86/88C and mine still shows the 20% mpg drop.

My best *guess* as of now is - the low mpg is either due to the low pressure EGR valve (EPDW type), pre and post NOx sensors, or a combination of the three. With no CEL, and given these are fairly expensive components (parts and labor), I am in a wait and monitor mode.

My real concern - if the engine is running "rich" (too much fuel exhausted as unburnt fuel), but still within the allowed levels (so no CELs), not sure what the effect is on the catalyst and DPF.

ard made a comment that if the engine is running properly, factory installed catalyst is good for 200-300,000 miles. I think he was referring to a petrol engine, not diesel . . .

Another interesting thing - I replaced the battery . . . it was almost 7 years old and I typically switch the battery around the midpoint of my intended/desired ownership horizon . . . after the battery was changed, the 4D16 code disappeared . . . no I didn't clear it, it just disappeared . . . now Carly returns a "0 fault codes found". Not complaining!

Quote:
Originally Posted by NickTheStick View Post
Subscribing for updates . . .

Having a similar issue with my 12' X5D. Currently at 51k miles. . . . Dealer . . . replaced the fuel filter. Noticed a ~20% drop in mpg. Vehicle sees 50/50 city/highway driving. . . .

Just ran a diagnostic via carly. Idle coolant temp is 181.4F, (83C) which is acceptable. Everything I have read thus far points to a faulty thermostat as the culprit for low MPG.

What also interesting is that I have a ghost code for 4D16. First time I've seen this. Looks like its been there for about 700 miles, which is around the time I had the fuel filter replaced. Wonder if there is any connection?

Maybe I should give BlueDriver a try? Im going to clear the code and see if it comes back. . . .
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