My Geo Prizm 1991 likes to overheat...

And I think it's mostly that the engine is old. If I sit at a red light too long, the temperature guage needle will show that the temperature has risen over the halfpoint. If it goes up further, the fan will kick in. Someone here said that the fan waits until it detects 100 Celcius before it kicks on. Is this true?

Is it possible to change the settings so that the fan will come on at a lower temperature, so as to prevent the needle from going halfway? I know it isn't a failure with the needle, because I recently had the sensors (is that what they are called?) replaced. Also, whenever the needle goes beyond the halfpoint my car shows other signs of getting too hot, such as vibrating harder. Not a nice thing. Makes me nervous. And how am I supposed to drive it around in the summer like that? It will be overheating more intensely and more often.

My question is, is there a problem with my fan? And if so, how do I fix it? And if there is no problem with the fan, then I will need to adjust the kick-on temp. How would I do that?

  aeroz19

t-stat maybe? not opening right or something..you leaking anything?, you have heat? im not a mechanic so wait til one knows about those cars :cool2:

  twoloud4urears21

100's high, but not un-common. Think of it this way, your thermostat doesn't open until probably about 90-110 degrees, depends on the thermostat you have in it.

What's half-way? what does the gauge read? because normally, half-way is where it is supposed to be. Just as long as it doesn't redline it's fine. It's cold in winter, so the car runs cooler, now it's getting warmer so you're car is starting to run warmer, is that all you're experiencing?

My car will go well passed the half-way point all the way up to 115 or 120, then once the thermo opens it'll drop to about 60. Coolant temp light stays on but it doesn't matter, as long as it doesn't get passed about 125 it's good.

  88GrandPrixSE