Overheating '92 corolla

[rickmadison]

Hi...,my 92 coroola witrh 175k miles on it is having this overhaeting problem lately. Normally the engine temp stays at around one third of scale while normal driving. Now as soon as I turned on AC, within 10 mins., the engine temp goes well above half level, close to red mark and then come back down little. Even I turned off AC, engine temp. never seems to stay normal (within third of scale) and oscillates in upper half of scale. This is a new thing thats happening this year. I replaced radiator last year. Appreciate your insight on this problem. Thanks-

[cuzman]

the thermostate is stuffed ..ther cheap and easy to replace!

[Tercel GTS]

That's something you should get checked ASAP.
If you're a do-it-yourselfer start by confirming the temp gauge is correct then make sure the fans are both working properly.

[cuzman]

Good point! make sure the fans work right..usualy if the wire comes loose the a/c fan stays on as an emergency measure....that'll cool her down as well ..but still check the stat
if ya pull it out it should be closed...then put into boiling water..it sould open..

[punter]

Even the boiling water test can be inaccurate. For such an important a part thats less than $10 I never even bother testing them, I just throw a new one in.

A said above the most likley problem areas are.

~themostat
~themoswitch (controls when the fans come on)
~fan wiring
~coolent level
~radiator cap

Would be strange if its not one of the above.

[rickmadison]

Thank you all for replying. I do oil change myself but thats all I do. I will take printout of your replys and show it to a person who usually work on this car and we will go from there. Thanks once again-