I have a 2002 camery and I had to replace the radiator its was new. it ran find for about 2 months then my heater stopped working just blowing cold air I put a new thermostat in it and the temp gauge still goes up and down I think I got all the air out of the system I have went back 3 or 4 times to make sure but the gauge still goes up and down. could someone help me out on something it could be. Thanks All

 

and I forgot to tell you if I turn the heater or air on it will run hot Thanks Again

 

4-cylinder or V-6 engine?

When does the gauge go up? Stop and go driving, idling?

The temp gauge also goes up if the heater or air is on?

 

4 cylinder when driving and if you turn the heater or air on it will run hot

 

Try setting the climate temp setting hot and cold while having the blower on and off.

Determine if blower on /off changes the engine temp gauge response.

With engine cold, check coolant level in radiator. Should be to the top of fill port.

Make sure the overflow tank has the proper amount.

How hot did the engine get, into the red? Any possibility of a blown head gasket.

 

ill try that Thanks toyomoho