What should your RPM at idle be?

[MDavis]

I recently had a motor rebuilt an can't get warm idle rpm below 1000. Is this normal what's the process to check.

Idle on scanmaster shows 00
Tps at .42

Should I set IAC again?

 

[pacecarta]

i

 

[Buick Mark]

Sounds like you have an "idle air" leak somewhere that the idle air control valve cant control. Stock idle is whatever is programmed into the chip. Usually 750/850 rpm.

 

[earlbrown]

I recently had a motor rebuilt an can't get warm idle rpm below 1000. Is this normal what's the process to check.

Idle on scanmaster shows 00
Tps at .42

Should I set IAC again?

If you mean IAC = 0 then the ECM is trying to bring the idle down and it's as far as it can go. If you have no vac leaks you need to close the throttle blade some (and reset the TPS back to .42) OR you need to verify the IAC pintle and socket are clean. If there's crud in there it can let in too much idle air.

It could be something dumb like a bad PCV that's letting too much air into the system (among other things as well)

 

[MDavis]

Done thanks!!
Blade open too much.

 

[earlbrown]

Always nice when the fix is an easy one.

I'm sure Mr. Murphy will make you pay next time! lol