I have a 2009 Chevy Cobalt bought used a year ago from a dealership near me. It has about 81,000 miles on it and just recently started messing up. My coolant temp will start heating up to about 200F-206F when idle. The normal running coolant temp I had logged before all this was 190F. Then, whenever I start moving from a standstill, my car will lose the ability to accelerate with ENG PWR REDUCES message on readout. I'll park and turn off engine wait a while and turn it back on and I can drive again with coolant temps around 200F.

Does anyone know what could be causing this?

Taking it to AutoZone tomorrow to get codes. Just thought I'd ask.

1 Answer 1


On GMs the only time the engine power reduced message is displayed is when there's a fault with the electric throttle, throttle position sensors or the accelerator pedal position sensors.

Depending on mileage and the code you may need to have a throttle service done.

Personally I wouldn't worry about engine temp running around 200*F. if it's a concern you should check the radiator fins and the cooling fan shroud for fit. As well as coolant level and condition.

There shouldn't be any correlation between coolant temp and your engine reduced power message.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .