I have 1984 C4 with Crossfire. My idle was rolling and kept stalling at lights. I changed the IAC valves after doing some research. Now I cannot get the idle back down to normal. When cover the air holes where IAC valves are I can bring the idle down to about 1000 rpms in neutral otherwise I am at 2600.
Any suggestions?
Thank you
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The IAC valves need to be "relearned". There is a procedure for this that requires a specific tool to block the valve(s) while doing it. I have the info at home I can send this evening if you want.
Joel Adams
C3VR Lifetime Member #56 
My Link 
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
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Yes. Thanks. That would help
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From the service manual...
Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
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Thanks. I will give it a try
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Replace the idle air control valve under the throttle body
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