Does anyone have an answer for this?

92stockbird

Registered User
I took my 1992 sc to Sims radiator for a flush and fill. When I went to pick it up, they said it runs hot, and that the fan runs when the AC is turned on.
I have no idea what was done to this car before I got it, as there:eek: is no documentation for what has been done, except for what I have done to it.
It seems someone wired something wrong, but I don't know where to begin to look.
Can anyone help? Please?
 
you really have not provided enough information for someone to help you, but I'll take a stab at some basics...

Im assuming the engine is actually running hot and that you dont have a bad gauge in the dash.

Im pretty sure the fan is supposed to kick on when the AC is turned on. this is to provide airflow over the condenser.

Now onto the car running hot... Its not very complicated how the system works. as the engine heats up the thermostat opens which allows the coolant to flow through the radiator to be cooled. once the engine is warm, the thermostat should be open and the upper radiator hose should be hot as hot coolant is flowing through it going to the radiator. If not maybe the thermostat is stuck closed or backwards or the wrong temp range. The engine coolant temperature sensor monitors the temperature of the coolant and tells the ECU what the temp is. Once the temp gets to the programmed temp 220deg, the ECU turns on the low speed fan, if it gets really warm 228deg, it kicks on the high speed fan. The ECU controls the fan via the IIRC which is the black box located behind the passenger headlight.

So those are the things to check...
thermostat
coolant sensor
IIRC
fan motor

you can use a test light to test the IIRC. unplug the fan and probe the terminals to see if its telling the fan to turn on... yes the engine must be hot to do this.

The coolant temp sensor is checked during a KOEO test so that is the easiest way to see if it is working. if you do the test with the engine cold, it should say out of range and with the engine warm it shouldnt through the code.

I already mentioned how to check the thermostat, if you suspect it, go ahead and replace it. they are not that expensive.

you can test both high and low speeds of the the fan by powering it straight off the battery. one pin is ground and the other two are the high and low speeds.

the other guys around here are probably more help, but this should get you started.
 
The fan is supposed to run when the AC is turned on. As far is it running hot they may not no what there talking about. Do a complete and proper bleed of the cooling system (which may take several days) and then see where your at.
 
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on both of mine fan runs with ac on . when mine ran hot radiator was clogged or balancer spun and timing was retarded
 
Ask them what "hot" means? According to the dash gauge? Or did they read the temp with one of their gauges? Or does the engine just seem to be hot after running it bit? These engines do seem to put out a lot of heat after running/idling, more than the typical car - you can really feel it when you pop the hood or even just being near the front of the vehicle. If everything is working properly, the dash temp gauge usually reads straight up, but shouldn't go past the "M" in NORM.
 
I have a 92 as well and I guarantee you there is still air in the system. Buy a radiator cap with a red burp lever on it and burp the air out right after driving it until no air comes out. Air gets trapped at the state housing and it causes all kinds of havok.
 
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