'97 Cavalier Temperature Gauge Goes Up & Down?

Question

I was driving my car and all of a sudden the temperature gauge went past the Hot point, and my "check gauges" warning came on. 5 minutes later, the "Check Engine" light came on and the temperature gauge dropped all the way down to cold. for the rest of the ride it would go all the way up, and then all the way back down. Do i just need to replace the thermostat or could it be something more serious?

Answer 1

my buddy had the same problem in his cav. it is low coolant, but while your servicing the coolant i would change the thermostat too, they are less than 10 dollars. and what ever you do dont put strait water in it.

Answer 2

I would take it in and have it checked, just to make sure you don't have a more serious issue. You don't want to be driving and have it die on you out in the middle of nowhere.

Answer 3

A shorted sensor wire will make it read hot and a loose sensor wire will make it read cold, but what you're describing is usually just low coolant. The liquid level drops below the sensor and it doesn't read right. It's not the thermostat. Engine temp doesn't change that quick.