Thread: Temp gauge problem after coolant temp sensor change.

I changed the coolant temp sensor this weekend in my '01 GP, refilled with Dexcool and bled the system. My temp gauge on the dash now reads incorrectly. When I start the car, the gauge reads 160, but then slowly climbs up to 260 and stays there regardless of engine temp. It was 28*F this morning, and the gauge was pegged at 260 within two block of my house.

Later today I will hook up a scanner to the ODBII port to see what the PCM is seeing for temp. When the gauge pegs out, the fans do not come on...so I am thinking that the sensor wiring might be the culprit, or I have a bad sensor.

Has anyone else experienced something similar?

I'd say you got a bad sensor.

I just changed one on saturday and they do suck because of the tight space.

Scanner shows that the PCM is seeing 195*F when the gauge is pegged at 260*F. Time to take back the crap Napa sensor and order an AC Delco.

When it comes to sensors on this car, OEM is your only option for correct readings. Also the temp guages are known to be off from the factory.

I used a napa part, it worked just fine.

They are known to be bad out of the box all the time no matter the brand really, cheaper parts being more prone to the issue.

Originally Posted by Fivefingerdeathpunch

I used a napa part, it worked just fine.

They are known to be bad out of the box all the time no matter the brand really, cheaper parts being more prone to the issue.

But with actual GM brands, those failure chances are reduced by even more to basically none. You don't hear a lot of people say their Delphi or Delco sensor didn't work out of the box. It's more of those cheap off brands on RA.