[335iee]

Hello all,

Need all you seasoned e90 experts. I’ve searched across the forums but still need help. Disclaimer - I am not a car expert so I apologize if I don’t use the correct terms etc...

Car: e90 335i Manual Transmission 130k mi

Symptoms: Car died on way home, battery light on, car cranks, engine turns on but keeps dying.
Repairs done:
Replaced battery with new one.
Low Pressure Fuel Pump replaced (Mechanic diagnosed this to be the problem)
Result: Engine and stayed on 20 minutes then died. Same as before, cranks but engine keeps dying.

LPFP has been tested and confirmed to be working

CODES: (Used Foxwell NT520 Pro)

9319/not present - KOMBI fuel-level sensor. Left

2A2D/not present - DME Fuel pressure

2AAF/not present - DME Fuel pump, plausibility

2E8E/present BSD. message: intelligent battery sensor (IBS) Missing

DME Fuel high-pressure system, fuel pressure

DME Smooth running, segment timing

9DB/not present - DME: Smooth running, segment timing

2DE5/not present - DME: Fuel level sensor, right. Signal

2DE4/not present - DME: Fuel level sensor, left: Signal

A6CF/present - JBE: AUC sensor


The codes don’t appear consistently - last 2 scans I ran only show:
2E8E/present BSD. message: intelligent battery sensor (IBS) Missing
A6CF/present - JBE: AUC sensor


Anybody with similar situation or can point me in right direction? Thanks in advance guys!

[dpaul]

Is your battery light still on?

[335iee]

No battery light on, thanks for the reply.

[dpaul]

Tough one. The persistent codes would not affect the vehicle running. So your car is dying without throwing any relevant codes.

The "not present" codes might not be related at all to your current problems - they could be years old and just weren't cleared. Do you know when the last time codes were cleared was?

When you say "engine cranks but keeps dying", do you mean that now it stalls very quickly after starting or do you still get to drive for 20 minutes before it dies?

[dpaul]

Just guessing but feels like an electrical problem - DME grounds perhaps. This kind of thing can be a real bear to track down.

[335iee]

Originally Posted by dpaul

Tough one. The persistent codes would not affect the vehicle running. So your car is dying without throwing any relevant codes.

The "not present" codes might not be related at all to your current problems - they could be years old and just weren't cleared. Do you know when the last time codes were cleared was?

When you say "engine cranks but keeps dying", do you mean that now it stalls very quickly after starting or do you still get to drive for 20 minutes before it dies?

I cleared the codes each time after running auto-scan with my Foxwell NT520 pro. The persistent codes from last 2 scans:
2E8E/present BSD. message: intelligent battery sensor (IBS) Missing
A6CF/present - JBE: AUC sensor

The very first time after fuel pump was replaced, the car was driveable for 20 minutes. Now it just stalls right away and dies.

Could this be the HPFP? I know the HPFP has been replaced before on this car.

[N52bigblock]

Probably check the IBS sensor connections then and make sure there'sno corrosionon it. A faulty or disconnected IBS can cause a lot of electrical issues. I'd be starting there for sure.

[dpaul]

neilj35 - disconnected IBS will not stop the engine.

OP - it could be a lot things, including the HPFP but you don't have a clear indication of anything and the HPFP is a $500 part. If you are depending on a mechanic to do the work for you the replacement will cost quite a bit more.

Its true that you have seen fuel related codes but 1) they are inconsistent and 2) none of them specifically relate to the HPFP. 2AAF for example is a code that many see episodically and if detected alone, is not a concern. You did see 2A2D, which is probably why your mechanic thought there was a low pressure circuit fuel problem - wouldn't necessarily be the LPFP but at least it's a plausible conclusion.

Yes, there is one HPFP related error message from Foxwell which is "DME Fuel high-pressure system, fuel pressure". I just have to ask WTF does that mean? Where is the actual high pressure circuit related code?

Also, how does one explain the other seemingly unrelated codes (fuel level sensors) and the IBS?

Again, if there is a consistent failure to achieve proper pressure levels on the high pressure rail, as you would have with a failing HPFP, why aren't the fuel pressure codes coming up every time you start the engine?

That leads me to consider an electrical problem. One often sees clusters of codes with a grounding problem, perhaps in this case a ground circuit that is a common point for IBS, fuel level sensors and LPFP. You can do some research at https://www.newtis.info/tisv2/a/en/. Check out the wiring diagrams that include this components and see if there is any common element.

However, that said, the first thing I'd do is to obtain the appropriate software to log some parameters while the engine is running or ignition is on. So you can actually monitor what the high and low fuel pressures are, or what the DME thinks they are. MHD is an relatively inexpensive ($100) way to do that. You'll also need a DCAN cable ($45 at bimmergeeks.com). While you're on the bimmergeeks site, I'd download BMW standard tools (INPA, NCExpert, WinKFP) and Rheingold (free). I much prefer INPA or Rheingold to a standalone device like the Foxwell to obtain error codes. They won't make up any bullshit or confuse your vehicle with a Toyota. They will also allow for activation of various functions you might like to test and Rheingold gives you a nice database of component locations and procedures (information that is also available at newtis.info).

You can throw parts at this and maybe you'll get lucky but that almost never worked for me. I feel that collecting more info by logging is the safest way to proceed.

Hopefully someone with relevant experience will chime in here

[335iee]

That's some very insightful and really helpful information there dpaul. Thanks. Wondering if any other owners have encountered the same issues?