Hopefully someone else has encountered this problem. My temperature gauge quits working, thereby causing the cooling fans to run for a couple of minutes when I turn the car off. From my understanding and research, the fans run as a precaution because the computer thinks the car is overheating. Well, mine is not overheating as far as I know. During the spring and summer when the outside temps are warm/hot, my temperature gauge works just fine. However, when the outside temp drops below 70, the gauge quits working.

I believe my temperature sensor needs to be replaced. Anyone else have a better, more technical opinion? And how much teardown is needed to change out the sensor? Thanks!

 

No teardown is needed to get to the coolant temp sensor. It's located right below the t-stat on the LIM. It might not be bad though. If you have access to a scanner, I'd check your coolant temps with it first. I say this because the coolant gauge on my dash will quit working sometimes, but I also have an Aerforce gauge and can read the correct coolant temp with that even when the dash gauge isn't working properly. This tells me that the sensor can't be bad, at least on my car...

 

Well something is not right, because the gauge only stops working when the outside temp drops below 70. For example, during the summer I have no problem. But for instance if we have a day where the temp cools down to the 60s, the gauge will go dead. And I noticed recently, when this happens the A/C quits cooling. Recently this happened and the next day was a warm day up in the 70s. The gauge was still dead and I had the A/C running when the gauge began working again. Immediately the needle moved up to where it should be and the A/C starting cooling.

And I think I found where the sensor is, but I couldn't get a wrench to it.

 

The A/C stops working because the car thinks something is wrong, and automatically shuts down the A/C to prevent over heating.

I had a similar problem with my Monte 3.5L...My gauge would drop to zero and the fans were on full blast ALL the time, and the A/C did not work. It only happened when the temp outside was in the 50's or below. Turns out that all this havoc was being caused by a bad thermostat. A rubber seal on the t-stat somehow cracked, and was causing the t-stat to be stuck open. Which when its cold outside causes your car to "over cool" itself, and for some reason caused a crap load of issues with the cooling system/ computer. But once i replaced the t-stat, all problems went away.

This could be your problem...for you its a super simple, $15.00 part, that never hurts to change anyway.

 

Thanks for all the great information! I kind of wondered if the thermostat might be the problem. I'll check it out.

 

I'm having exactly the same problem on my 2000 Monte SS 3.8ltr. Thank you for advice. I'll change T-Stat.