1989 750iL idle problem

My 1989 750iL, will not idle smoothly when it warms up. Once warm the idle
rpm varies 600 to 1100 rpm, and occasionally turns off.

> My 1989 750iL, will not idle smoothly when it warms up. Once warm the idle
> rpm varies 600 to 1100 rpm, and occasionally turns off.

I believe these are known for leaking inlet manifold gaskets. That would
let unmetered air into the system and mess with the idle.

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It's probably a vacuum leak. Check the intake manifold gaskets.
"papajo" > wrote in message
lkaboutautos.com...
> My 1989 750iL, will not idle smoothly when it warms up. Once warm the idle
> rpm varies 600 to 1100 rpm, and occasionally turns off.
>

John and Magicrat, thanks for the respond, I'm trying to figure out why my
750 suffers from an erratic idle problem. I checked for leaks in the
intake air tubing and found none. I then noticed that the idle runs at 500
to 600 RPM and stable for the first 20 minutes, after that the idle is
erratic from 600 to 1100 and occasionly truns off.
I'm thinking that the 500 to 600 RPM at idle may be too low. What do you
guys think?

thank
papajo

what is the best way to check for vacuum leaks in the intake manifold
system??