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523i is M52TU not M54 and that answers the fuel pressure regulator mystery.
Do you have gas? E39 is notorious for bad fuel level sensors!

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My bet is on clogged fuel filter that overworked the FP and eventually killing it.
My guess.


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Discussion Starter · #23 ·
Do the starter fluid test as bmw blue suggested. If it does start then you can start looking at why the fuel pump isn’t working. Your fuel pump relay should be behind the glove box. There are 2 fuses in the fuel pump circuit.
Both fuel pump fuses #17 and #31 are OK. I would like to have a look at the fuel pump relay, but to do that I need to remove the glove box as far as I understand.
That will be next logical step after I test the fuel pump at the tank itself.
Could a faulty fuel pump/plugged filter generate the two failsafe error codes or could it be that the engine failsafe mode is shutting down the fuel pump?
 

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Discussion Starter · #24 ·
523i is M52TU not M54 and that answers the fuel pressure regulator mystery.
Do you have gas? E39 is notorious for bad fuel level sensors!

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Plenty of fuel. I refueled 60 l a week go and have been driving less than 30 km since then.
 

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Just curious, is you e39 a left had drive? I’m not familiar with your country flag.
I wouldn’t think you’d get 2 Failsafe for one problem.
 

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If that engine is an M52TUB2.3 then you have the MDK throttle body which is a hybrid cable operated and electronically controlled throttle body. When they go wonky they can go into trans fail safe mode but I do not think fuel will be shut off. Quick question, is there a throttle cable attached to the throttle body..?
It’s odd with the euro models, for instance, my 2000 528I with the M52TUB2.8, it has a 3-way valve for the fuel system, separate fuel filter and the fuel pressure regulator valve is within that 3 way valve underneath the car.
On my car, the fuel pump relay is in the trunk on the right hand side fuse/relay block above the battery.
 

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Discussion Starter · #27 ·
Just curious, is you e39 a left had drive? I’m not familiar with your country flag.
I wouldn’t think you’d get 2 Failsafe for one problem.
Yes, it is left hand drive and I am currently in Thailand.
 

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Discussion Starter · #28 ·
If that engine is an M52TUB2.3 then you have the MDK throttle body which is a hybrid cable operated and electronically controlled throttle body. When they go wonky they can go into trans fail safe mode but I do not think fuel will be shut off. Quick question, is there a throttle cable attached to the throttle body..?
It’s odd with the euro models, for instance, my 2000 528I with the M52TUB2.8, it has a 3-way valve for the fuel system, separate fuel filter and the fuel pressure regulator valve is within that 3 way valve underneath the car.
On my car, the fuel pump relay is in the trunk on the right hand side fuse/relay block above the battery.
The throttle body could very well be the cause of my misery. Certainly worth investigating. The OBD scanner might reveal if there is a throttle fault.
Is the throttle body the black box in the below picture?
They moved the fuel relay from the trunk to the front right hand side sometime around 2000. I only have 2 relays in the trunk, but 3 in the front.
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Discussion Starter · #29 ·
First thing I would do is pull off the back lower seat, have someone turn the key to the 2nd position and listen to the pump to hear if it primes or not for a few seconds, also I would get some starting fluid and see if it will fire up by getting some starting fluid down that intake, if it fires, then you have spark. Odd that you have the fuel regulator at the front of the fuel rail.
What engine size is your car, this should have been the 1st thing listed in your thread.
Not a drop of fuel and no auditable sound coming from the fuel pump with the key in position 2.

The key question: Is the Engine Failsafe Prog. shutting down the fuel pump or could a failed fuel pump promt the error code?
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Just put 12v straight on the pump and see if it dead or just cut off. Thick
And do replace the fuel filter.... it's like breathing with a clogged nose.
Wiring diagram for the pump here.
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Your throttle cable rubber sheathing is totally gone exposing the now rusty innards of the cable, thats not good. Improper cable operation from wear and tear and being out of adjustment on the MDK throttle body can cause issues.

The fuel pump relay location changed in 2001 at some point as seen below.

I gotta say, you have an oddball M52TUB2.3 being in a 2002 model year.

This is why it is so important when posting to know and describe what year, model and engine exactly you are talking about. I thought it was an M54 and you stated you believed it was.

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Maybe you know this, but the MAF is disconnected in your pic.
He knows. Part of his diagnostics from post #1: "3. Disconnect air mass meter."
 

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Discussion Starter · #35 ·
I did as suggested and connected 12 V direct to the fuel pump: plenty of fuel coming out, pump is working.
I then reconnected the fuel line and gave the fuel pump 12 V again and voila plenty of pressure at the fuel rail. The car cranks fine, but still not starting.

With the key in position 2 the DME is having voltage, 11 V over 85-86 in above schematic, but 0 voltage to the pump 30-87. This is a strong indication that the car has shut down the fuel pump as part of the Engine Failsafe Prog to protect the engine.
In summary, the fuel pump is fine and the root cause of the error codes is somewhere else, but where?
Throttle seem the logical next step, but where to start and how to test?
All and any suggestions are welcome and deeply appreciated.
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Next step is to read and clear the codes and see if they return or if the fail safes are triggered again. Our suggestions are to change the fuel filter and vacuum lines while waiting for the scan tool.

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So let's tackle one problem at a time: the crank-no-start...

The throttle and the MAF (mass air sensor) have nothing to do with the car cranking and starting or not. Idem for those fail-safe messages: that is history, error codes stored in the memory of the ECU. It is not the cause of the no-start.
Did you check or replace the fuel filter ??

As (if) the battery/starter (electric) and the fuel pressure (pump/filter/lines) are apparently ok, we can speculate on the EWS/DME loss of synch. But you need a BMW specific scanner, to prove it or not, fix it, and get a handle on the problem.
 

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Discussion Starter · #38 ·
So let's tackle one problem at a time: the crank-no-start...

The throttle and the MAF (mass air sensor) have nothing to do with the car cranking and starting or not. Idem for those fail-safe messages: that is history, error codes stored in the memory of the ECU. It is not the cause of the no-start.
Did you check or replace the fuel filter ??

As (if) the battery/starter (electric) and the fuel pressure (pump/filter/lines) are apparently ok, we can speculate on the EWS/DME loss of synch. But you need a BMW specific scanner, to prove it or not, fix it, and get a handle on the problem.
I think you are onto something there Chedley. It could very well be the EWS security system shutting down the car.
Now that you mention it, I have been using the backup key as the open button is broken on my main key. It was always hit and miss if they backup key would remotely unlock the car and most often I had to stick the key in the lock to open the car. I always just thought the internal key battery was just weak as I haven't used that key for many years.
Out of pure desperation I tried the EWS bypass trick below, but the car is still not starting, let alone sending 12 V to the fuel pump.

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That is the warning chime speaker.

It is possible that the CPK (Crankshaft Position Sensor) has failed on your car. You need a scan tool, if you cannot somehow get some codes and read them, you are just chasing your tail. If you get a code reader, you can set it to RPMs and crank the engine over, if you get no RPM reading while cranking, the CPK is dead. What happened with getting some starting fluid, again, that will tell you if you have spark/ignition or not.

A failed CPK will not allow the fuel pump to operate.
 
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