Hey everyone, ive been trying to troubleshoot my retarded idle for awhile now and im just about out of ideas. To start, ive got an ls/vtec setup, gsr head, and JG intake manifold. It idles at ~1500rpm, and surges sometimes, but not often. I found out the IAC was leaking, so I tried every sealent out there and I changed the o-ring for a new one. Same problem. Ive sprayed the entire intake area with intake cleaner and cant seem to find any other leaks. Ive adjusted the idle screw and it doesnt help. What am I missing?

thanx

 

and I also tried a P72 and chipped P28 ecu, no difference.

 

Did you try replacign the IAC itself, the motor will fail without setting a CEL, same problem I had, swapped to another one, problem went right away. . .

Of course after I put the intake manifold gasket on and throttle body chasing the motor the whole time

 

it could be a number of things:

bubbles in your coolant
iacv
fitv
vaccuum leaks