Re: @$#%@! - it's not the AFM! (archive)

My M6 did exactly as you describe, except did not ever backfire. When cold, slow throttle response until fully warmed up. I suspected all the things you've mentioned to no avail. Fixed the problem by having the valves set by a very talented mechanic that owns an 88M5. Engine runs like a dream now. HTH

Well, car acted up again with the swapped AFM, so that's not the problem. Here's a real clear description of what it did: I'm in 1st, apply throttle, car acts like it is pulling a 2 ton weight, RPMS go up but reluctantly and car just doesn't want to go. I keep it 4000 rpms, car goes but again, I can feel I have a lot more throttle applied than I normally would to drive at a constant 4000 in 1st. Suddenly, after 20 secs or so, rpms zoom up past 5000 and car of course accelerates (without me moving the throttle - in fact I almost have to back off on throttle lest it redline). I shift to 2nd, and boom there is a small backfire when throttle released during shift. Then it drives fine. This ONLY happens when engine is stone cold and I drive away immediately. It also seems to only happen when the air temperature is say 45-70 degrees??!!? SO seems temp dependant, but I've put in a new coolant temp sensor, and swapped an AFM, which of course has the air temp sensor.
I have also checked the coolant temp sensor at the ECU plug, seems fine.

This is driving me nuts, my mechanic is baffled. Still offering a beer shipment (your choice) to anyone who hits upon a possible cause that I haven't tried...

Follow Ups:

Re: @$#%@! - it's not the AFM! Todd Kenyon 19:01 11/10/2001 (1)
- Valve clearance ian M635 UK 01:59 11/11/2001 (0)

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