97 cavalier

#1

WHY DOES MY TEMP GAUGE AND MY HEAT GO COLD AT SPEEDS OF 60MPH OR MORE? P.S. 2.2 LITRE WITH 166,000 MILES ON IT.

#2

Your engine uses a temperature regultaing device called a thermostat,I would start with that.

#3

Please check the coolant level in the radiator (when cold), and consider having the cooling system flushed and refilled and a new thermostat installed. Your car is old enough to need a new thermostat, and they are not expensive.

#4

I already changed the thermostat, and flushed out the heater core. somebody suggested the head gasket, i hope this is not the case.

#5

Not likely headgasket (different symptons for headgasket) for you sounds possible you have air in cooling system (sending unit not in contact with coolant)

#6

So try “burping” the cooling system. This might help:

#7

already tried burping no change, also as the tempature gets cold outside,the engine does too. somebody please help me!!!