[Fletcher737]

Good evening all I hope you are well.

I am new to the forum and a new and proud BMW owner as my first car.

I recently purchased a E92 325i, 56 reg, auto, 96k miles and have one major issue.

The car has the above error codes (my friend has the snap-on diagnostic tool, not sure what model but he uses it in his garage) and has diagnosed the 3 in the title, 2D06, 29E1, 29E1, the CEL is on, and reappears once reset and cleared.

When I start the car the car wobbles/ shakes slightly and you can hear the engine going up and down in revs, it jumps up to maybe 1k/1.1k revs then fluctuates for 20/30 seconds between 600/1k then drops just around 500, the car sounds like it wants to stall then it settles at 600.

I recently did a 45 mile journey in the car and the car seemingly stalled, I put my foot on the accelerator and received no input, I turned the car off, put into park then back into drive and it drove fine with no issues.

This has happened 3 more times over an hour long drive where I had to restart the car, however I took it for a 1hr30 drive yesterday and the car ran perfectly and didn't stall once.

I have used Holts Easy Start spray and could not find any leaks within the engine bay, I have changed the air filter and the issue still persists, however when I unplugged the MAF sensor the car ran a lot better, not perfect but a lot better at idle, no more rev jumping.

I have ordered Liqui Moly Air Flow Sensor cleaner to see if this will help remedy the issue and I am thinking about getting a smoke test done to see if any vacuum leaks could be the issue.

I am wondering if anybody has had these issues before and if anyone could please assist!

Thank you all, and I hope to share my journey with everyone on here

[therealdb1]

Sounds to me like you have done the diagnostics already.
With those codes it sounds like an internal fault with the MAF. Cleaning it won't help.

In your position I'd be tempted to source a second hand genuine one from a breaker since they are silly money new.
A word of caution with someone who has the T shirt only fit a genuine BMW MAF. Don't waste your money on Chinese copies on ebay and the like because they will not last 5 minutes and you'll be back to square one!

The car will run with default settings without it connected so it will not run great but it won't keep stalling either.

I'm not sure what live data you can see on the Snap On reader but if you have something like INPA / ISTA or Carly you should be able to see what temperature the MAF thinks the intake air is which might confirm the fault before replacing it.

[Fletcher737]

Thanks!

And yes I know, I think the Continental or Siemens MAF's are around £150/200 but the only issue is I don't want to throw parts at it without 100% knowing what it is. The MAF installed currently isn't either of the two above so hopefully that's the issue and not a leak.

I'm going to have a love at some breakers yards nearby to see if they can help also before buying a brand new one!

Thanks for the reply

[therealdb1]

Thought they were normally Bosch or Siemens but either way if you don't have an OEM MAF fitted that is probably your problem right there!

These cars are particularly fussy about their sensors. You can fit aftermarket mechanical parts but anything electrical stick with the genuine article otherwise you are asking for a headache! Just look at the number of posts about LED lightbulbs!

You may have an induction leak also (although I feel unlikely) which is possibly the reason why the previous owner fitted the MAF you now have but I would change the MAF first and see how you get on. You may just avoid that migraine!

BTW If you are going to be a 'hands on' owner it is well worth getting your own BMW specific diagnostics tool. In comparison to other manufacturers products they are remarkably cheap. For example, the ISTA suite will do everything you are likely to want to do including coding and all it will cost you is for a lead to connect the car to a Windows (7 or later) laptop.

[Fletcher737]

I tried a new MAF it was a bit better but did not fix the problem.

I have tried doing as much as possible myself but I have it booked into a specialist German Car garage next week, all parts and labour under warranty though so its all good!

Thanks for the help!

[Cornheiser]

Originally Posted by Fletcher737

I tried a new MAF it was a bit better but did not fix the problem.

I have tried doing as much as possible myself but I have it booked into a specialist German Car garage next week, all parts and labour under warranty though so its all good!

Thanks for the help!

What was the fix?

thanks!