Hello, My Son has a 96 Avenger 2.5 and it was low on anti-freeze. It does not run hot at idle (no matter how long and the fan cycles on and off). If you drive it at all, the temp will continue to climb. Is there anyway to identify if it is a clogged radiator, the water pump or a head gasket? There is no anti-freeze in the oil, I do not smell any anti-freeze at the exhaust pipe. The water pump was replaced with the timing belt at 70K and the car now has 135K. This is very frustrating... Thanks

 

I'd replace the radiator cap and thermostat ...I'm guessing that either the cap is weak or the thermostat is stuck ...

 

I'd say check the cap and thermostat like bad venge recommends. If this won't help, flush the system. Hope there is no air in the system!

 

***Update*** installed the new thermostat and cap and have the same result. I did notice that the heat is not hot either (since my son never mentioned this) and also the top hose is hot but the lower hose is ice cold... I am thinking the radiator is clogged up? This car does sit a lot since he is in college and only uses it while he is at home. Any help greatly appreciated!