Ok thnx to those who replied to my first message. I drive a '98 2.8. My car over heated. I changed the thermostat and water pump. Afterwords I drove it the next day overheated again and the highway patrol who passed by showed me that my fan clutch was worn out. Ok I changed that now too. And drove it to make sure. It overheated again. I'm Borrowing someone elses car right now but when I get home I'm gonna try to fush out the radiator since I used 2 bottles of the stop leak stuff about half a year ago. if I squeeze the lower radiator hose I can still hear the pressure change from the expansion tank. Well if it's not any of these things, what's causing my car to overheat???

 

Oh Christ, stop leak was your first mistake. Hopefully that's not what did it.

After changing/refilling coolant, did you burp the system?

 

no, honestly, i don't know what you mean by burp the system or how to do it. we've already tried to flush the system and it seemed to work a bit, we drove it around today and it heated above normal operating temperature but didn't reach overheating temperature. but this was at night after it had rained so the air was very cold. how do i burp the system?

 

There's many posts on this forum and a section in the DIY on how to burp the system yourself.

When the car is at normal operating temp, temp gauge should be at 12 o'clock.

And I have a post on this forum with pics of what happens to a heater core with only ONE bottle of stop leak in it (heater core replacement is an 8-10 hour job, BIG $$$$)....it will also start clogging your radiator, water pump, thermostat etc after awhile and you can NOT get it out....that stuff should be illegal!!!

Remember, an Audi is a German Car, built differently than a US car....stop leak in an AUDI causes alot of problems!!