I have been having an issue with my 2001 convertible where it randomly overheats. The fan is running when it should and is running the correct direction. This started after I replaced an extremely old thermostat shortly after buying it over a year ago. I was a bit naïve and didn't know about the burp valve until I looked it up in another forum. I followed the instructions to a tee and it still was overheating. I then replaced the water pump,*radiator cap, put in another new thermostat, and flushed the system. I cycled through a few times of filling at the burp valve, running until hot, letting it cool, and repeat, until the burp valve seemed to be topped off. I thought I had it beat, but after sitting for a little over a month, it overheated again earlier this week. I let it cool and opened the radiator cap and burp valve and repeated the process again. I only added less than a quart, but it has not overheated since (just idling in my driveway every day for about 30 minutes). I am thinking my radiator might be bad, but I have no identifiable leaks and no puddles of antifreeze. I am thinking of just going ahead and replacing the radiator because I do not know what else it could be. I'm a bit confuse because the*radiator overflow tank is still full and has not released any coolant into the radiator. *I know I am getting air bubbles in the system because*every time it has overheated,*the heater has blown cool air. After topping off the burp valve, it blows hot again. Any ideas, guys?

 

Does it only overheat when the a/c is turned on?

 

My Son's was doing it, then the Thermostat stuck closed, and it kept on
over-heating. Start there, just replace it, it's cheap enough, and doesn't
take long. There is an air-bleeder on the top of the thermostat housing,
block side. It's a bolt, you loosen that up to burp air.



You only need to loosen out a few threads while the motor is running.