[Cartrax]

My "84 has a vacuum issue which I'm having a difficult time resolving. Today I tried the cigar smoke test and found both the IACs leaking from the back where the motor is housed. Do I need to replace them or is that typical of a good IAC?

[toobroketoretire]

Originally Posted by Cartrax

My "84 has a vacuum issue which I'm having a difficult time resolving. Today I tried the cigar smoke test and found both the IACs leaking from the back where the motor is housed. Do I need to replace them or is that typical of a good IAC?

First of all what makes you think you have a vacuum issue? Are you seeing a real low vacuum when you put a gauge on it? What kind of symptoms does your engine have?

I have never heard of any IAC being the source of any vacuum issues so I suspect yours aren't causing any issues either.

Let me know what's happening and I'll do what I can to help you find the problem.

[Cartrax]

Originally Posted by toobroketoretire

First of all what makes you think you have a vacuum issue? Are you seeing a real low vacuum when you put a gauge on it? What kind of symptoms does your engine have?

I have never heard of any IAC being the source of any vacuum issues so I suspect yours aren't causing any issues either.

Let me know what's happening and I'll do what I can to help you find the problem.

Thanks for the reply - They're leaking, definitely. Reading is ~10" hg at idle. Leak is coming from the back where the step motor and metal housing meet. I mean you can blow air through "em. Trying a temp solution - slapped some gasket sealer back there to see how it runs now that I know that no air should be getting through. Will be a bit before I try this cuz I'm waiting on a new brake booster which was also leaking. Will take another reading and post results, thanks.

[toobroketoretire]

Originally Posted by Cartrax

Thanks for the reply - They're leaking, definitely. Reading is ~10" hg at idle. Leak is coming from the back where the step motor and metal housing meet. I mean you can blow air through "em. Trying a temp solution - slapped some gasket sealer back there to see how it runs now that I know that no air should be getting through. Will be a bit before I try this cuz I'm waiting on a new brake booster which was also leaking. Will take another reading and post results, thanks.

You are aware the IAC motors aren't a part of the throttle bodies, aren't you? As the black 4-pin plastic plugin is formed into the front of the stepper motor housing and the stepper motor housing has threads on the rear of it to screw into the throttle body I don't see any way they can possibly leak other than around the threads if the gaskets aren't in place or they're not tightened.



Try tightening them first and see if that stops your vacuum leaking......................

[Cartrax]

Originally Posted by toobroketoretire

You are aware the IAC motors aren't a part of the throttle bodies, aren't you? As the black 4-pin plastic plugin is formed into the front of the stepper motor housing and the stepper motor housing has threads on the rear of it to screw into the throttle body I don't see any way they can possibly leak other than around the threads if the gaskets aren't in place or they're not tightened.


Try tightening them first and see if that stops your vacuum leaking......................

Might be one for the books. Not one but both IACs were leaking through the body, reason I asked if that was normal. Showed up as I pumped smoke into the manifold. Whatever seals the step motor to the metal housing apparently deteriorated. I mean you could blow air right threw the body. Sealed "em with some permatex black - will see how long that lasts.

Attempted to add picture but I'm not up to ten posts yet.

[Cartrax]

This is number 10 one more and maybe we'll get the picture here.

[Cartrax]

OK # 11 - Bingo here's the pic....

[toobroketoretire]

I'm looking at the IAC in my hand and I can't see how it's possible to leak between the plastic plugin and the metal housing but if it could leak there I sure can't imagine it leaking very much.

What exactly is your problem? Poor idling quality? Poor performance? Missing? Is your CrossFire lid sealed with a gasket or silicon? I have found silicon is the only way to go as it'll never leak.

[Cartrax]

Doesn't look like I'm going to convince you but they were leaking badly. I usually hang out at the Crossfire Injection Forum where there's a long thread on the issues I'm having. Took the shotgun approach on this question and went out to several forums looking for some diverse opinions. Thanks for responding.

I decided to put the IACs back in today and take it out with the brake booster port plugged just to see how it runs. Will post results here too.

This is thread on CIF - always looking for help from the knowledgable folks such as yourself...

http://crossfireinj.5.forumer.com/in...75&#entry26356

[toobroketoretire]

Originally Posted by Cartrax

Doesn't look like I'm going to convince you but they were leaking badly. I usually hang out at the Crossfire Injection Forum where there's a long thread on the issues I'm having. Took the shotgun approach on this question and went out to several forums looking for some diverse opinions. Thanks for responding.

I decided to put the IACs back in today and take it out with the brake booster port plugged just to see how it runs. Will post results here too.

This is thread on CIF - always looking for help from the knowledgeable folks such as yourself...

http://crossfireinj.5.forumer.com/in...75&#entry26356

But you still haven't my question. What kind of problems are you having? Poor idling quality? Poor running above idle?