[torrque]

Originally Posted by FEDE/E92

Have you checked your tmap?

yes, I mean I cleaned it and put it back... do you think that could cause the problem ? I would buy a new one and change it if there is a any remote chance of problem with it.

Here is a log I ran today. Strange how my low pressure fuel sensor is having a drop when I am asking more , accelerating , see rpm are increasing... most logs I am seeing show sort of flat line low fuel pressure sensor. Mine has these spikes ; and I also see a high request from fuel pump. Now it could be either EKPM or low pressure fuel sensor ?

Oh, and I also have now code 2AAF "fuel pump plausibility" in the DME stored.. But it came when I disconnected the O2 sensors and ran without them to see what happens, as I was suspecting them for a while (same stuttering, so I know it's not them).

Thanks for any feedback.

https://datazap.me/u/mhainal/log-151...=8-9-20&solo=6

[FEDE/E92]

I would start with your codes. Don’t have a friend with a 335i, swap parts really quick.

[Works]

Have you ever pulled your LPFP or logged LPFP when this happens? A dirty fuel tank can cause these types of issues.

[edit] Didn't see that you changed the LPFP and HPFP. Still there is a minor chance that you have crap in your tank that can cause the fuel feed to be starved occasionally, how this could happen only on a warm engine is not consistent with this type of an issue.

[torrque]

Originally Posted by Works

Have you ever pulled your LPFP or logged LPFP when this happens? A dirty fuel tank can cause these types of issues.

[edit] Didn't see that you changed the LPFP and HPFP. Still there is a minor chance that you have crap in your tank that can cause the fuel feed to be starved occasionally, how this could happen only on a warm engine is not consistent with this type of an issue.

How do I log LPFP apart from the one that is in MHD ; is there another parameter to log ?
Thanks

[Faredo]

I didnt see you mention it, have you had a look at the cam angle sensor?

[torrque]

Originally Posted by Faredo

I didnt see you mention it, have you had a look at the cam angle sensor?

Honestly no, never gave me any codes, will check. Must be on top somewhere, right ? Edit: I found the sensors, right and left to the vanos solenoids... If they are error free, would one change them ?

I also cleaned the vanos solenoids the other day, and they looked fine... I mean the car is high in mileage (100k) but I know it has never been boosted.

[Works]

Originally Posted by torrque

How do I log LPFP apart from the one that is in MHD ; is there another parameter to log ?
Thanks

MHD logging was that I was referring to, especially looking at dramatic pressure undulations when this behavior is present. If the LPFP pressure nosedives it could be either an issue with the pump (as it has been changed, unlikely), pump power delivery or clogged in-tank filter sock. If you fuel pressures are steady when the car shudders, then it must me something else.

[torrque]

Originally Posted by Works

MHD logging was that I was referring to, especially looking at dramatic pressure undulations when this behavior is present. If the LPFP pressure nosedives it could be either an issue with the pump (as it has been changed, unlikely), pump power delivery or clogged in-tank filter sock. If you fuel pressures are steady when the car shudders, then it must me something else.

AFAIK, the pump is driven by the EKP module, is that a possibility ? I bought a second hand one, which I can code with NCSexpert, and test with that... It came from a totaled 2009 E92, so it's a EKPM3.

I do see some drops in pressure, as low as 75 to 44PSI when the hickups happen. So I'll test the EKP first, then maybe change the Low pressure sensor, that one seems to be original, never changed... Sensor is a bit unlikely, as it would behave the same hot or cold, and my problem only starts when *something* warms up.

Many thanks

[musa]

Since you have INPA, even if you're not getting codes, look at the historical codes. You might find something in there. When I had similar symptoms as yours, at times no codes would be thrown but I would find codes in the history even if I cleared it. That could be the breakthrough you're looking for. Take a look.

[torrque]

Here is one thing I am concerned. At 5 PSI of boost, low pressure rail drops to 44 PSI, and throttle opens and closes withing a second or 2 frantically there ....
I didn't log the accelerator pedal, but I am sure I was flat down or close to, not modulating. This is not normal:

[Works]

Originally Posted by torrque

Here is one thing I am concerned. At 5 PSI of boost, low pressure rail drops to 44 PSI, and throttle opens and closes withing a second or 2 frantically there ....
I didn't log the accelerator pedal, but I am sure I was flat down or close to, not modulating. This is not normal:

Post that to the MHD log thread?

[torrque]

Still chasing this.... low pressure sensor swapped, no change. I am waiting on delivery of new coil packs, and will report back after swapping those. They seem to be very old, someone swapped only 3 out of 6, and some go back to 2008 as age. I would have expected a misfire though if coil pack was to blame?

[Nexus313]

Alternator?

Edit: NVM you said you did that. Are you sure the dme was programmed correctly? Where did you have it done.

[torrque]

Originally Posted by Nexus313

Alternator?

Edit: NVM you said you did that. Are you sure the dme was programmed correctly? Where did you have it done.

I tested it with an alternator disconnected and overnight charged battery.. Same issue. New coil packs, same issue. BUT, I did a water pump bleed procedure to hear it running, and it is horrible. It sounds like a fan where you put a stick or something between the blades, pretty much dying (it starts up like a dying frog ) . I am waiting on water pump and thermostat delivery, will replace those next. It could be a parasitic current draw when pump starts causing engine to stumble; which explains lack of codes, as DME is also affected. It also happens when it warms up, which kind of makes sense as pump only starts when coolant warms up a bit.

We shall see soon...

[torrque]

Water pump and thermostat swapped... took me a whole bloody day to 9 PM...
New pump is quieeeeet as a small mice chewing. Still shaking and bucking like always.

I am losing my battle with this car, it is the first vehicle I am unable to fix after months of logging/swapping and error checking. It has been at 2 shops and nobody could find the problem... I think I will just split her an sell for parts. Stay tuned...

[deeLow]

Originally Posted by torrque

Water pump and thermostat swapped... took me a whole bloody day to 9 PM...
New pump is quieeeeet as a small mice chewing. Still shaking and bucking like always.

I am losing my battle with this car, it is the first vehicle I am unable to fix after months of logging/swapping and error checking. It has been at 2 shops and nobody could find the problem... I think I will just split her an sell for parts. Stay tuned...

Not for nothing man, but why not just take it to the stealer?

[torrque]

Originally Posted by deeLow

Not for nothing man, but why not just take it to the stealer?

I already did !, They said " low pressure sensor and coil packs" . Changed both, no difference ( I knew it won't make any, nothing points to a fueling problem, and I have no misfires).

Every time they make in investigation they charge 160, no matter if they are right or wrong... It's only so much you can absorb

[musa]

Ok, in my case I almost sold the car because nothing would fix the limp mode issue with the car bucking violently- I was in exactly the same situation you're in at this juncture. Finally a new DME was installed and instantly the car was 100% perfect and continues to be to-date. Later I learned that completely recoding/flashing the DME would have also fixed the root cause - that may require a dealer visit. Try that. Please don't give up just yet.

Good luck!

[Nexus313]

Originally Posted by torrque

I already did !, They said " low pressure sensor and coil packs" . Changed both, no difference ( I knew it won't make any, nothing points to a fueling problem, and I have no misfires).

Every time they make in investigation they charge 160, no matter if they are right or wrong... It's only so much you can absorb

Find a really reputable stealership, and when you go in ask for the service manager and explain your situation in detail and specifically everything you've done so far before they lay a finger on your car. You gotta make it clear and let them know or they'll come back with the typical "coils, spark plug, injector" shit.. Ask them to really test your DME (because they can do this) and wiring harnesses to dme for proper continuity. You might think its not your dme or harness because you just had it done already, but there's a big chance that that still could be the culprit. For ex; I had an o2 sensor issue, changed to a new o2, and boom the issue still existed, this time with even more issues! Turns out the new o2 I got was crap also, and I was digging into other shit for no reason! Just verify.

Trust me man, you've been through so much parts and work already might aswell not give up & just hang in there.. Just have the DME and shit 100% verified by a well-reviewed stealership. Ask around in your local FB groups on their experiences. Besides, you've done a whole lot of major maintenance in this process, your cars gonna be good if you can fix this.

[MJ80.]

Ill say it again i had this violent bucking and jerking and it was fixed with a flash tune of mhd. Never had it again and this shit was crazy wild, i pulled my procede and went mhd ans it was gone. 100% this has to be ecu/flash/wiring related.

[torrque]

Thanks all.. I tried stage 1 from MHD immediately when I got it, and it was the same, still shaking. Due to higher levels of boost it felt even stronger when it cut off, so I took it off and flashed stock again.

I spoke to BMW of Boston again, and explained their diagnosis was wrong, so they are willing to look at it again for a reduced rate; they are keeping it for longer this time and giving me a car to drive around. See what happens next; but I am not bringing my hopes up; I trusted German Performance more than the dealer, and they could not fix it, had it there for almost 3 weeks (a dent appeared in my bonnet meanwhile, so I was kind of pissed when I picked it up also.... ).

[Nexus313]

If that doesn't work, I think I found something new..

if you watch this video, you'll see that when he disconnects his low pressure fuel pump wires, his car still starts but will stall after a little bit.

I know your car probably doesnt stall this quick, but it's worth getting the wiring harness on the fuel pump looked at aswell.