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Old 02-04-2013, 06:29 PM
schpenxel schpenxel is offline
Location: Greensboro, NC
Join Date: Nov 2009
Posts: 3,436
Mein Auto: 2004 545i
Are those the only codes? I have never seen a fuel trim error on mine.

I would think fuel trim errors would be related to vacuum leak(s) and/or O2 sensor issues.

I never did figure out what mine is caused by--the weird thing is it runs PERFECT if it's under somewhere around 25*F outside. It's only when it's right around freezing that it goes all crazy. Above somewhere around 40* it doesn't do it either. Very strange

I have cleaned my MAF but haven't tried replacing it. I know there is some sort of switchover that the valvetronics system does the first 90 seconds it's running. If I understand it correctly, the valves are actually opening all the way (like a normal engine) when it's first started and the computer uses the throttle body to control RPM. Then it makes the switch over from throttle body to valvetronics.

I need to do some more googling and make sure that's correct and how it actually does it, but I feel that mine is related to something in that process, I'm just not sure what exactly..

Last edited by schpenxel; 02-04-2013 at 06:33 PM.
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