Alright I need help! I’ve got a 2018 equinox that I’m now having significant cooling issues with. It had started off with a water pump that needed to be replaced. (Fins were damaged) as well I replaced the thermostat just to be safe. About 2 months later the car started to overheat again after about an hour of driving. Took it to mechanic and he said he flushed the heater core and it looked fine. Still overheating so i decided to take a look at the thermostat again. It turned out to be faulty and wasn’t opening all the time. Replaced it with a new one that I verified was working. After that was done I put everything back together. But now after about 10 mins of driving the temperature with spike and then go down. I am absolutely confused on what’s going on. Any ideas would be greatly appreciated
2018
Chevy Equinox
premier 1.5L

 

First you should have bought a GM original thermostat if you didn’t already, also use your vin. Some cars will have different thermostats for different temperatures. Also, you CANNOT EVER bleed a cooling system on a modern engine especially a turbocharged one by “burping” the hoses, it needs to be vacuum filled, any air pockets will cause overheating.


If none of that helps verify the engine coolant is actually overheating with a mechanical temp gauge, remove ECT sensor and install the correct fitting, connect your mechanical temp gauge and drive slowly, check temp and verify sensor data is correct.


is any coolant leaking or just an overheat condition?

Also just a friendly word of advice, almost every modern mechanical thermostat is designed to fail open. If you are testing it by putting it in water or heating it that is an improper test and doesn’t mean it failed.