Crossfire owners*High idle problem

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Mar 14, 2003 | 11:17 PM

hgpreston

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From: Greenbrier TN

Crossfire owners*High idle problem

Just bought an 82 Model and it's idling at about 1100rpm in gear when warmed up. Any thoughts or anyone know of an adjustment. Pics would be very helpfull if there is an adjustment point. Thanks alot. (Yes I know this is the C4 tech area but I hoping to find an 84 owner that's had this problem) :confused:

Mar 14, 2003 | 11:37 PM

buzzbomb

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From: Urbana IL

Re: Crossfire owners*High idle problem (hgpreston)

My high idle problem was a vacuum leak at the back of the manifold cover, near the EGR valve, this is a common place to have a leak. I found it by spraying carb cleaner and listening for a change in idle, but if you do it this way, do it in a well ventilated area, the fumes are nasty. Also have a fire extinguisher handy, just in case. Could also be IAC valves sticking, etc.

Mar 14, 2003 | 11:53 PM

hgpreston

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From: Greenbrier TN

Re: Crossfire owners*High idle problem (buzzbomb)

Thanks for your help. Any chance you could send a pic of the IAC so I'll know where they are. I'm familier with them on tuned port motors but this crossfire is all new to me. Have you had any other crossfire problems?Thanks

Mar 14, 2003 | 11:58 PM

CFI-EFI

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From: The Top of Utah

Re: Crossfire owners*High idle problem (hgpreston)

It sounds like it is getting extra air from somewhere. Check everywhere for a vacuum leak. I have heard of others having a problem with the manifold lid to base gasket. You could make sure all the bolts are tight. A gasket replacement may be necessary. Of course all the other normal sources should be checked also. Possibly, a build up of carbon is preventing one of the IACs from closing down sufficiently. TB to lid gaskets are a less likely possibility. Use all the typical techniques to check for vacuum leaks. The lid gasket is the only item exclusive to the Crossfire. I HAVE seen a miss adjusted TV cable prevent the full closing of the throttle. There IS a base idle setting operation, but it is unlikely this is the cause.

Currently, I have a 2200 rpm idle speed and 15" of vacuum in my crankcase, but that's a whole 'nother situation. Even though it is the infamous Crossfire, it really isn't all that unique in operation. Good luck, and...

RACE ON!!!

Mar 15, 2003 | 12:04 AM

buzzbomb

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From: Urbana IL

Re: Crossfire owners*High idle problem (hgpreston)

They are on the fronts of the throttle bodies, toward the drivers side on bot, I think, they are big and have a wire connector going into them, should be pretty obvious. I can get a picture tomorrow if you still need it. :cheers:

Mar 15, 2003 | 12:28 AM

CFI-EFI

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From: The Top of Utah

Re: Crossfire owners*High idle problem (hgpreston)

Buzzbomb posted and you responded while I was composing my answer.

Quote:

I'm familier with them on tuned port motors but this crossfire is all new to me.

The IACs are similar to those on the TPI. They are located as Buzzbomb pointed out, and they each have a 4 wire electrical connector plugged into them.

Mar 15, 2003 | 12:33 AM

buzzbomb

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From: Urbana IL

Re: Crossfire owners*High idle problem (CFI-EFI)

I bought my '84 with 149K miles, cleaned the IAC's replaced the O2 sensor, replaced the TPS, and finally replaced the manifold cover gasket. The gasket was the only real problem, now it runs great, no problems at all. :cheers: