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bimmerod
08-31-2005, 01:11 PM
My 95 318is is periodically searching for idle when I stop.
Seams to run okay, but when I stop it's jumping back and forth from 500 RPM to 1,500 RPM.
Any ideas?

JazzM
08-31-2005, 01:29 PM
There are several possibilities here. The first and least expensive one is that you have a vacuum leak. Another possibility is that your idle control valve is gone. Those go for under 200 at the dealership. Finally it could be your AFM. To check that just disconnect the cable while the car is running and see if that idle RPM jumping continues. Good luck!

Best regards,

T.

bimmerod
08-31-2005, 01:33 PM
Thanks T.
I'm not sure if this is related but, if the car sits for a couple of days, it wants to stall when I first start it. This has been happening for a while.
Vacuum leak? I guess look for loose hoses.
AFM?
Thanks
R

JazzM
08-31-2005, 02:40 PM
AFM is your Air Flow Meter (aka MAF - Mass AirFlow sensor).

If its a vacuum leak its a hose or clamp that's broken/loose. could also be the intake manifold.

Most likely I'm thinking its the idle control valve. this valve closes when you're driving and opens while you're idling (your throttle body closes all the way shut - air still needs to get in the engine or it will stall).

Regards,

T.