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Washburn
01-20-2009, 11:01 AM
I have a 1215 code - mass air flow sensor. Does anyone have a procedure to test this? I did do a search first.

1995 525iT M50

Thanks!!

Morgenster
01-20-2009, 11:06 AM
I have a 1215 code - mass air flow sensor. Does anyone have a procedure to test this? I did do a search first.

1995 525iT M50

Thanks!!

There's an easy way and a hard way.
Ther easy way is less precise: disconnect it and start the car or disconnect it when running. See what happens.
The hard way involves measuring resistances and stuff. You'll need a manual like Haynes or other for that.

Dave M
01-20-2009, 04:17 PM
If you don't have a DMM (Digital Multimeter), get one. They're cheap and indispensible, even for the electrically challenged such as myself.

http://img.photobucket.com/albums/v11/dave_macisaac/Bimmer/Misc/MAF_1.jpg

http://img.photobucket.com/albums/v11/dave_macisaac/Bimmer/Misc/MAF_2.jpg

http://img.photobucket.com/albums/v11/dave_macisaac/Bimmer/Misc/MAF_3.jpg

Dave

JD525IA
01-21-2009, 04:00 PM
I have a 1215 code - mass air flow sensor. Does anyone have a procedure to test this? I did do a search first.

1995 525iT M50

Thanks!!


but I recently had the same code on my 1992 525i and I tested the MAF with this procedure, cleaned it with special MAF cleaner, cleaned the idle control valve, and finally failed emissions.

Turned out that my catalytic converter was bad. Luckily, the state of Arizona has a clean air program that paid for all but $150 for the new cat.

The code went away after I passed emissions.

Try getting some MAF cleaner and do the tests in the book. Hopefully you don't have to do what I did.

JD

Washburn
01-21-2009, 08:28 PM
Thanks for the test procedure. The wire cleaning burst is a quick and easy first check.

I put a new set of plugs in, and it's a fair but better. I really have my doubts about the MAF thing. Idles very rough, smooths at steady throttle. misses and chugs at partial throttle. Since replacing plugs, it misses at throttle tip in, then smooths out once power and revs build. Still chugs at idle. Wierd.