Idle Problem. Please Help

[panicos]

Originally Posted by pwpanas

Have you checked for boost/vacuum leaks? If a boost/vaccum leak exists around the intake plenum area, it can (inappropriately) function as a secondary IACV. If your Supra uses a maf, this additional unmetered air will cause an over-lean condition at idle.

Also note that some boost leaks, especially ones in the intercooler piping, can partially seal up when hot, due to expansion of the couplings, clamps or intercooler pipes.

This is the only thing I have not checked 100%. It might be a cracked hose. I have to spend a few hours searching for leaks and this what I am planning to do asap. Do you have any idea about the sensors that have effect on the way IACV works?. There is also a vaccum hose connecting the intake plenum with the throttle, do you have any idea what it does ?. Cant find if there is a crack on it. I will get some Samco Vaccum hose and replaced as may as I can. This might help.