I ran into a problem of an overheating motor a few days ago. I checked under the hood and notced the fan was not running, I checked the fuse which was good and I switched the relays from the air conditioning and the cooling fan which had no effect (they were the same type of relay) I drove the car home and noticed that at anything over say about 30 MPH the cooling system functions properly and also noticed that when not moving the AC compressor kicks off and the car runs really sluggishly, but when it gets back up to speed the temp returns back to where it should be and everything else functions properly as well, it is a 99 cavilier with a 2.2 L and a 5 speed manual, has about 120K miles. Any help you could offer would be greatly appreciated, thanks a ton!
Try testing the coolant temperature sensor and fan motor and wiring -also could be that the computer is not compensating for the load from the AC to demand the IACV to raise the idle or the IACV itself. Other sensors such as IAT/VSS/AC control switch/AC pressure sensors that the computer uses to energizes the relays.
September, 19, 2007 AT 7:33 AM
It seems that the fan was bad and that is what was causing all of this mess, thanks a ton! You hit it rigt on the head and as a side note, I also know from browsing the other questions that I need to pick up a blower motor resistor to fix a problem I have had since I bought the car! You guys are the best! Thanks again!