4.0 high idle

I have a 88 cherokee 4.0. So far I`ve replaced the TPS and IAC. Cleaned the throttle body a hundred times, and still every once in a while when I start it, it revs. to high and stays there for to long. I`ve cleaned the connectors, maybe not good enough, I don`t know anymore. There`s not that many vacume lines. Any ideas would be great!!!!
MIKE

[xjy173]

Have you checked the throttle linkage itself? it may be sticking a little. You have already replaced the IAC, the trouble could be in the ECU sending a voltage signal to the IAC. If the voltage is incorrect it will throw off the amount of fuel that the injectors squirt into the combustion chamber and causing a high idle due to a rich mixture, kind of what happens when a carbureted engine has the choke closed when it first starts. Hope this helps, and Good Luck!