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

I have experienced the same problem you describe. It fustrates me, too. However, since it only happens when the engine is stone cold, I've used it as kind of a leash for myself until the engine has warmed up. I always try to keep the RPMs <= 3k until the coolant temp gauge gets out of the blue range. From there on, I allow myself more and more throttle until I feel that the engine is up to operating temperature and ready for full bore accellerations. Have fun!

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:

[ Follow Ups ] [ M5 (E28) Message Board ] [ Msg. Board FAQ ]

Questions, comments, or problems, please visit the Roadfly help desk.