I have 1997 Camaro with a LT 1 it idled fine when I got it then it blew a head gasket I tore it down and replaced the head gasket and now it idles between 1500-2000 rpm. I checked all the vacuum lines and replaced the ones that where bad and it stll idles high.I put an under drive pulley,cold air intake,and header's when I put back together too.I took it to a friend and put on a computer and it shows it's missfiring on 3,5,6.What could be causing this problem.

 

Deal with the misfire first and maybe it will go away with that. You did a lot of different things at once, so hard to say what you missed. Go back and check your work on anything you had apart or replaced.

 

Intake leak. Did you dig the old plastic out of the heads from the intake gaskets?

 

Thanks for the info. I was wondering if the miss may have something to do with it.