Temperature gauge not working properly

FRANCODADI

MEMBER
2013 CHEVROLET MALIBU
2.4L
4 CYL
2WD
AUTOMATIC
250,000 MILES

Overheat alerts on dash display with temperature pinned to the hot side of the gauge. I had just started the car. Not even warm yet. The fan is in full blast mode coolant in the tank and circulating, no leaks, the belt is fair and no noise from the water pump. After shutting off and cooling down for 25 minutes the temperature is back to normal. After I drove for a few minutes, the temperature gauge rose quickly and bounced between norm and hot. This is weird, never had this happen before. The hoses are warm to the touch.

3 Replies

SQM

MECHANIC
6,383 POSTS

Hello,

It sounds like you might have a faulty coolant temperature sensor.
The temperature sensor sends signal to the gauge and also controls the cooling fan. As it is showing 'hot' it is triggering the fan to cool down the engine.

Here are some helpful guides:

https://www.2carpros.com/articles/how-a-coolant-temperature-sensor-works
https://www.2carpros.com/articles/symptoms-of-a-bad-coolant-temperature-sensor
https://www.2carpros.com/articles/coolant-temperature-sensor-cts-replacement

I have attached a diagram for your reference.

Let me know of any questions.
Thank you.

Image (Click to make bigger)