idle issue... [Archive] - Bimmerfest - BMW Forums

: idle issue...

Cali Love (e34)
10-15-2008, 01:54 PM
there might be another thread on this but i could not find it,
randomly when i go to start the car (cold or hot) it starts but the rpms go to about 1500 then down to 150-300, when its low the CEL comes on then rpms go up and the light turns off. but about 20% of the time when this happens the car will not stay on when the rpms drop. im pretty sure its the MAF sensor but not positive (i removed and cleaned connection to intake already but didnt seem to help) ive had this car a little over a month and its my first bimmer just wondering if anyone has run into this before. thanks

10-20-2008, 03:04 AM
My 91 525i m50 had same problem. Combination of parts finally fixed the problem: New MAF, new IAC valve, fixed vacuum leak, new fuel filter, and new 02 sensor.

10-22-2008, 05:06 PM
I've had similar prob with a different car.

I would start with the MAF. Stalling issue could be caused from that and might as well change the fuel filter because its cheap and easy. IAC from my experiences causes a surging that might not be the issue...definitely look for vacuum leak.

Good luck :)

Start with the cheapest parts first...then go from there. Sounds like MAF to me tho.