e34 525i AFM/stalling issue....

[Thin Air]

Well, I have a 92 525iA (non-vanos M50 engine), it liked to stall out for no reason when pulling away from a standstill. I checked the simple things like coils, plugs, filters, etc. Everything was in check, or recently replaced. I then moved my way over the air-flow meter. If I disconnect it the car runs practically flawless. It'll still try to hesitate every now and then but I'll rarely stall. So I borrow another used AFM and try it, still the same problem. So the next logical step is to try out a spare ECU I have access to. Again still the same problem.

Now the problem has gotten much worse, as soon as I touch the throttle the car stalls, whether it's in drive or not, and it only stalls when the AFM is plugged in. What are the chances of both AFM's being messed up??

Anyone have any input to this?

[fkong777]

have you check the rubber elbow? Between AFM and Trottle body? I removed mine and found cracks at the underside of the accordian flex section. Also the 2 vaccum inlet hole was cracked too.

It is hard to see without removing it. Since all the damage is at the under side.

cost about $35. Brought back a lot of response and power.

[Thin Air]

Yes, I checked the boot as well, there are no tears at all.

[Thin Air]

Turns out ignition coil #3 was arcing. I noticed this today (yes, a year later) when the car was idling without the ignition coil cover in the dark.