Mechanics

CHEVY COOLANT TEMPERATURE SENSOR

2007 Chevrolet Cobalt

Engine Cooling problem
2007 Chevy Cobalt 4 cyl Front Wheel Drive Automatic

I have a 2007 Chevy cobalt LS with a 2.2 liter ecotec engine, I am having problems with the coolant temperature sensor. I have replaced the sensor twice already and it continues to act up. It will not read when the outside temperature is below 60 degrees Fahrenheit. If I start it from a cold start then drive for a few miles it will read up to 170FÂ ° then it will hover around 165 to 170 then it will get stuck on a random temperature in between Then it will read ---FÂ ° followed by the radiator fan coming on and running constantly. After all of this happens the engine light will come on after a few more miles. Can someone please help me?
Avatar
Samms21
September 30, 2010.



When you replaced the sensor both times did it ever fix the issue?

Bluelightnin6
Sep 30, 2010.
No it never fixed the problem I thought I just purchased a faulty sensor but it continued with the same problem

Tiny
Samms21
Sep 30, 2010.
What type of coolant are you using in system or has it ever been replaced?

Bluelightnin6
Sep 30, 2010.
Coolant has never been replaced, it is the factory orange colored dextron

Tiny
Samms21
Sep 30, 2010.
Did more research and it seems to be a common issue with these Cobalts, although I am not finding a solution, however I have found that replacing the coolant sensor and replacing the computer has NOT fixed the issue in the past. Replacing the thermostat is what I am leaning towards, the tstat is around 20 bucks new and rather simple to replace.

Bluelightnin6
Sep 30, 2010.
Thank you for your help even if the thermostat is not the problem I am willing to risk 20 dollars.

Tiny
Samms21
Sep 30, 2010.
Yes, normally I don't throw stuff out there but the engine coolant reading is fairly simple set up and from all the research I read online and from what you have described it really leans me to the tstat. Let me know how it goes and if you need steps on replacing the tstat I can get those as well

Bluelightnin6
Sep 30, 2010.
Not exactly sure where the thermostat is on my car I was once told to follow the upper radiator hose and it should be at the end of that.

Tiny
Samms21
Sep 30, 2010.
The thermostat is located behind the engine under the exaust manifold on the drivers side. Just look for the water pump tube and you will find it.

Bluelightnin6
Sep 30, 2010.
Is eat easy to replace? Just unbolt and put the new one in or is it more complicated.

Tiny
Samms21
Sep 30, 2010.
Page 1 of 2