About 2 years ago, the wife's Cavalier (2200/auto) overheated on the freeway. Had the thermostat and radiator replaced. It overheated again shortly after. Thermostat was replaced again, still overheated. Thermostat was replaced a third time, and this fixed the problem.
Car has been fine for 2 years until it started running warm again, and eventually got to the point where it would almost overheat if left idling for any period of time. The radiator fan would come on, and barely keep the temp out of the red zone. Temp would come down some, but not all the way, once you get moving. Definitely not normal behavior, and would happen every time the car was driven.
On a hunch, given that we went through 3 thermostats before getting a "good" one, I replaced the thermostat again last weekend. Fired it up and had to shut it off before the engine overheated at idle. Radiator fan could not control the temperature at all.
Found no coolant in upper radiator hose. Added a gallon (all I had on hand) through the overflow reservoir and most of it got sucked down; reservoir stayed about half full. Must have simply not had enough coolant to control the temperature.
After doing this earlier today, I took it for a test drive. Three miles to get gas and 3 miles back; temperature stayed rock steady at the middle of the gauge. Problem fixed, I thought.
Turned the car off, went in and got the wife, and we decided to go to the store. By the time I had gotten back outside, the car had heat-soaked a bit and the gauge was reading higher than "normal," but I have the same car and this has always been typical behavior. Nothing to worry about, and it cooled down to halfway as we got moving.
Went on the freeway. Suddenly I watched the gauge climb steadily and by the time we got to where we were going, it was approaching the end of the "safe" zone. Parked, went inside for ~30 mins, and headed home.
When I started the car again to leave, the gauge was at 1/2 like it normally is. The whole way home, it stayed roughly at half, maybe slightly over, but where it should be. Did not overheat again.
Which leaves me wondering what happened.
Sticky (but brand new) thermostat? I'd believe it based on the fact it took 3 to get a good one last time.
Air in coolant? I let it boil over with the reservoir cap off after topping it up, so I would think I got any out.
New thermostat "break-in?" Is there such a thing?
Headgasket? I hear these engines like to blow them, but it seems unlikely given there is no oil in the coolant or coolant in the oil, the car is neither hard to start nor lacks power (well, for a Cavalier...)
I think for now I'll just monitor it and see if it comes close to overheating again. At that point I may just run it without a thermostat and see how it behaves. Outside temps are in the 100s for the foreseeable future so I don't think warming up will be a problem.
Or maybe I should just drain the ATF and replace the VSS. I'm sure that will fix my problem.
Car has been fine for 2 years until it started running warm again, and eventually got to the point where it would almost overheat if left idling for any period of time. The radiator fan would come on, and barely keep the temp out of the red zone. Temp would come down some, but not all the way, once you get moving. Definitely not normal behavior, and would happen every time the car was driven.
On a hunch, given that we went through 3 thermostats before getting a "good" one, I replaced the thermostat again last weekend. Fired it up and had to shut it off before the engine overheated at idle. Radiator fan could not control the temperature at all.
Found no coolant in upper radiator hose. Added a gallon (all I had on hand) through the overflow reservoir and most of it got sucked down; reservoir stayed about half full. Must have simply not had enough coolant to control the temperature.
After doing this earlier today, I took it for a test drive. Three miles to get gas and 3 miles back; temperature stayed rock steady at the middle of the gauge. Problem fixed, I thought.
Turned the car off, went in and got the wife, and we decided to go to the store. By the time I had gotten back outside, the car had heat-soaked a bit and the gauge was reading higher than "normal," but I have the same car and this has always been typical behavior. Nothing to worry about, and it cooled down to halfway as we got moving.
Went on the freeway. Suddenly I watched the gauge climb steadily and by the time we got to where we were going, it was approaching the end of the "safe" zone. Parked, went inside for ~30 mins, and headed home.
When I started the car again to leave, the gauge was at 1/2 like it normally is. The whole way home, it stayed roughly at half, maybe slightly over, but where it should be. Did not overheat again.
Which leaves me wondering what happened.
Sticky (but brand new) thermostat? I'd believe it based on the fact it took 3 to get a good one last time.
Air in coolant? I let it boil over with the reservoir cap off after topping it up, so I would think I got any out.
New thermostat "break-in?" Is there such a thing?
Headgasket? I hear these engines like to blow them, but it seems unlikely given there is no oil in the coolant or coolant in the oil, the car is neither hard to start nor lacks power (well, for a Cavalier...)
I think for now I'll just monitor it and see if it comes close to overheating again. At that point I may just run it without a thermostat and see how it behaves. Outside temps are in the 100s for the foreseeable future so I don't think warming up will be a problem.
Or maybe I should just drain the ATF and replace the VSS. I'm sure that will fix my problem.
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