Temp Gauge/ T-Stat

[renotahoe]

Hello fellow Tahoe drivers. I have a 2019 and I have already replaced the thermostat and temperature sensor and everything had been good for a short period period. Now occasionally when I start the car, the temperature will go up, sometimes willfluctuate and every once in a while will go back to zero and the fan turns on. Does this sound like I might have a faulty thermostat or a bad connection at the sensor. Thanks

 

[OR VietVet]

Did you replace the sensor/sender with a Genuine GM unit or an aftermarket? You can use some electrical cleaner and cleaner the male/female connector. Sometimes, just unplugging and plugging back in will clean the connection. Or, you may have a problem with the gauge. Do you have a live data scanner to monitor the temperature.

 

[renotahoe]

It was an Autozone purchase. I do not have a scanner. I was thinking that if I had a bad gauge I wouldn't have had the fans go into overdrive. So it seems like either a faulty T-Stat or the sensor. The T-Stat was AC Delco brand. That electrical connection on the sensor was not easy to get off. I will take a look again tomorrow, but thanks for the comments.

 

[OR VietVet]

Yea, I read about the fans and then forgot. Soulds like right track. Get a Genuine GM sensor, instead of a Duralast. Get a new connector and "solder" the connection. Then deal with whatever may still be happening.

 

[Joseph Garcia]

You've gotten some great advice here. Let us know the results of your next steps.

Also, just because, check the ground strap between the motor and the firewall, to ensure that the connections are clean and tight.

 

[jyi786]

If you got an AC Delco Gold, or anything other than GM Genuine, you have wasted your money. Yes, even AC Delco Gold will give you trouble.

Ensure that BOTH the thermostat and the coolant temp sensor are both GM Genuine. I just went through this myself. I changed the sensor and the entire thermostat housing and it fixed all my issues (no temp reading and fans spinning on max at all times, even with the truck off).

 

[renotahoe]

Fixed! All seems good now that I have installed the Genuine GM sensor. I am a little concerned as I have a AC Delco gold T-Stat though. I didn’t realize it wasn’t a genuine GM part. Will watch closely for issues. Thanks everyone for you responses.

 

[Joseph Garcia]

I'm glad to read that your issue is resolved. Please add the word "FIXED" or "SOLVED" to your thread's title, to let others who are experiencing a similar issue know that this thread has an identified solution.