hopefully this is an easy one for you guys i have read about 150 posts on the iac valve and cant find my answer. When i first start the engine it idles up and then steps down to around 750 rpm but as it warms up the iac will only move down to 39 but if i move the shifter just enough to turn out the p/n light on my scanner the iac will close if i dont move the shifter the idle will increase as the engine warms up untill i put it in gear then its fine.

 

TBI? The '747 & '746 do not control idle while in park/neutral. There
are only upper and lower bounds.

RBob.

 

yes sorry i didnt say it is a 747 tbi. now it makes sense i think thanks for the help

 

RBOB,
I am always seeing plugs for your IAC article on the GMECM board but can not find it ,and want to understand it better.
Can you shoot me a link?

Thanks

 

Sure thing:

http://www.diy-efi.org/gmecm/papers/

RBob.

 

I just realized that RBob is Rob Rauscher (sp).

I'm not worthy...

Rob, could you read/reply to my other post??? I'm gonna lose my mind.

 

Yes, yes, LOL, please, just change the R in Rob to B
as in Bob and it's all cool. Hmm, be the one on the
prop duration? I'll take a look at it.

RBob.