If any body can answer a quick question playing with my rough and high idling 5.6 I pulled one of the connectors of the coolant sensor and the system went into limp home but pulled the other one off and nothing happened? both reading the same output at operating temp any ideas. High idle at operating temp. 1000rpm @ 80 C but drops to about 700 in gear after reading most of the posts on this suject, my theory on a bad Fuel injection control modual is starting to sink. not concerned with rough idle but more with the rolling idle thanks for any help/advice. just dont understand how the box converts the temp signal out all the other devices that uses it. bad low temp would mean cold start valve running all the time?

thanks

The green/red wire on the temp sensor goes to the fuel system.

The green/black wire goes to the ignition system...not much change there.

The idle system on that car is a stand alone system(has it's own inputs)..doesn't receive info from any of either fuel or ignition systems.

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thank for the response I have all the diagrams for the wiring I just can not figure out why one would make it idle up and not the other, as in my prior post the temp signal is good all the way to the injection comtrol unit and my understanding is there should be 3.5 to 5 volts, depending on the coolant temp, that would go to the Idle control unit and then on to the fuel pump relay and so on. agian thanks for any help. Other than the chain slap, car ran fairly well untill I got my hands on it.