I have a 94 Eg with a 94 GSR with a S2 Pro series Manifold. Im having problems with a bouncing idle. When the Car is cold the idle jumps up to 3k then drops to 1k and as it warms up the RPM jump decreases to around 2K and drops to 1k or sometimes sticks 2k. There are no check engine lights either. I switch out two different IAC valves in replace of it and still the same thing. I put some PB blaster in the IAC valve to see if it would free up a possible sticking issue? still nothing? I checked the vacuum lines going to to the manifold and the idle didnt change?

any suggestions?

 

check for vacuum leak, what ecu are u running

 

you have totry cleaning your trotle body

 

check your valve timing.

 

Check vacuum leak at S2k manifold flange. Is the throttle cable adjusted correctly. Also what is the position of the idle set screw? Is throttle position sensor adjusted correctly? These are some areas of interest to you. Good Luck

 

well?