[dfrogers]

Hi All,

Having an issue with my E90.... the car starts and runs but after a period of time dies and then will no longer start after. It cranks and fires but instantly dies unless I put my foot on the gas but even then it dies.

I had issues with it stalling and dying and previously whilst driving (awesome BMW thanks) noticed a gas smell so figured I'd replace the pump and regulator in the tank. These are both done and after replacing I am still having the same issue.

I have also checked the battery cable, recall was done and it was done correctly....

I have tried unplugging the MAF and I get the same issue, same symptoms as above.

Car is JB4, FBO

Codes as follows:

29D0
2775
29D2
36BB
2714
28BA
28B0
28AB
2C70
2711
28D4

My next move is a smoke test, I have checked around the vacuums and it all seems solid but I cant think of anything else. Not going to replace the HPFP until I have tested everything else.

1. Could it be coild and injectors?
2. Could it be bad gas (Really???)?
3. HPFP maybe
4. Those codes all suggest its an intake pressure issue, could it be a faulty sensor?
5. Is there anything I need to do on the DME, reset or something? I have a MHD so could flash it to stock and see what happens?

Appreciate your insights all, this is seriously painful at this stage.

Thanks

[fastboatster]

you probably need to recheck your JB4 install. if you would look up the codes, you'd see that some are electrical like "2C70" - Boost pressure sensor, electrical: Short circuit to earth. Looks like there might be some wiring or JB4 issues. The car would absolutely not run with no MAP sensor.

[dfrogers]

Thanks man, going to remove it entirely and see how the car behaves. Might just use the MHD by itself.

[dfrogers]

Ok I checked some of the cables and honestly it’s messy, my MHD is struggling to connect which is making me think there is a problem with wiring. Further when I switch the ignition on (after clearing codes) limp mode triggers without the car starting or running. It then throws all of the codes so it has to be electrical. Ground straps and removal of the JB4 and check of the wiring are next steps.

Then if that doesn’t solve it I’m assuming DME might be in trouble…..

Any thoughts here are welcome, thanks chaps

[dfrogers]

I cleared all codes and let the car sit over night, it starts fine and idles fine. I didn't give it any gas but tried to set up some monitoring on my MHD,

Fuel pressure looks good
Battery voltage looks good its in range

Monitoring did however throw a check engine, specifically when I selected RPM as a measure. My sense is the monitoring is triggering a fluctuation in current and is triggering something. So this is 100% looking electrical at this stage.

If I had given it gas I am sure it would have triggered the fault, increased current etc.

1. Not fuel
2. Not Ignition

Next steps

1. Remove the JB4
2. Check wiring for damage
3. Check the ground straps
4. Check voltage from Alternator

[Benzinfa-Lo]

Hello,

Have you been able to solve your issue? I have some thing similar, cleaned T-map, maf sensor, changed throttle body, but still I get these codes, engine cranks up hard, after some time dies off. Car is stock, only chargepipe.has been changed.
1. 2714 - Throttle valve, function: Sluggish, too slow.


2. 28AB - Throttle valve, potentiometers 1 and 2: Double fault.


3. 28B0 - Consequent reaction: Throttle valve: Emergency operation mode active.


4. 28BA - DME, internal fault, activation of throttle valve: Internal communication fault.


5. 28D4 - Throttle valve, adaptation: Teach in again, bottom stop not taught in.


6. 36BB - DME, internal fault, software reset: Malfunction.


7. 387F - Power management: Standby current violation.

[konstat]

Originally Posted by dfrogers

I cleared all codes and let the car sit over night, it starts fine and idles fine. I didn't give it any gas but tried to set up some monitoring on my MHD,

Fuel pressure looks good
Battery voltage looks good its in range

Monitoring did however throw a check engine, specifically when I selected RPM as a measure. My sense is the monitoring is triggering a fluctuation in current and is triggering something. So this is 100% looking electrical at this stage.

If I had given it gas I am sure it would have triggered the fault, increased current etc.

1. Not fuel
2. Not Ignition

Next steps

1. Remove the JB4
2. Check wiring for damage
3. Check the ground straps
4. Check voltage from Alternator

Without seeing your logs it's tough to say but have you considered replacing intake manifold and charge pipe MAP sensors? What about your throttle body, does it look dirty and/or does it need to be replaced?

Also, if you could specify the descriptions output by MHD for those codes that would be helpful. I normally look them up but not when someone has 11 codes

[dfrogers]

Ok so I had some pretty major vacuum leaks on the intake pipe and also on the turbo inlet. These have been fixed and the car runs and drives.

In addition I removed the JB4 which has resolved the DME comms issues I seemed to be having.

We are now on to a new problem which I think is related to the EKP. When the car first died months ago I got the fuel pump warning on idrive. This has since never come back since replacing the LPFP and the Regulator, but after a drive around 10 mins the car stalls, it then will not start until its cooled down.

This seems to be a common symptom of the EKP, I think the failing HPFP which went on for months caused failures in the LPFP and potentially overheated the EKP?

I have an EKP on order, used from Ebay to see if this resolves things.