I have been having issues with my '97 2.8 AFC overheating. I tried replacing the thermostat and flushing the system a few times, and have also replaced one of the sensors (the one on the back side of the radiator, driverside of the car).

If I drive with the heat on it will drop back down to regular operating temperature after a little while.

I have also noticed that the electric fan on the passenger side of the radiator doesn't seem to turn on. I thought it might be broken, but I hooked it up to a seperate power source to check it and it still works fine.

Any suggestions? The only other thing I can really think to change would be the water pump, but I don't know if it seems like that is what is causing this problem.

 

did you have any of the belts replaced recently? an older belt could wear down on the motor causing it to overheat. timing belt idoler and water pump. are the things i would look for.

 

Could be that one side of the radiator is blocked.....

 

^^^agreed.

 

Sounds like you've got some sludge built up in the radiator. Pull the hoses and flush it to seewhat comes out. If its really bad, nissens offers a great radiator for the money.

 

PS, also check the fan relay if you suspect the fan doesn't turn on.

 

The passenger side fan is the AC fan so that shouldn't matter I don't think. As for the flush, I had one done on a prior car along with a pressure test for $25. It's inexpensive enough that I'm tempted to take the radiator out of my A4 and have it done the next time I put the car in service position.