OK, first post is not the best, my apologies. I have a 1996 Audi A6. Everything is great....right. As I am sitting there setting the radio stations and seat positions, steam starts coming out from my overflow tank and the coolant is boiling out, but every gauge in the car read fine. Then the "coolant light" starts flashing on the dash board. Not so great anymore.

I called the dealership I bought it from, "bring it back" he says. He swaps out the aux. fan and gives it back. That night, same problem. So I take it back. He puts in a new thermostat and a new cap. It still does it. So I take it back again and he was thinking maybe there is a crack somewhere in the overflow tank letting in air, replaces it. Get it home, still doing it.

A little more on the problem. Right when I start the car, it's fine, and can sit all day idling. Driving down the road it is fine as well. The problem only happens after the car has been driven for a while, and then idles for about 2 minutes. The gauges all read fine until it actually starts overflowing coolant, then the light flashes, but the temps still read OK.

I'm dreading the following: Water Pump, Radiator, Head Gasket

Any input is greatly appreciated, I have always had good luck with forums.

 

If its not overheating its a fat chance the thermostat/water pump isn't working correctly, more than likely the coolant resivior cap is bad or the expansion tank itself is leaking when it gets hot.

 

Thanks, t stat, cap, and tank have already been replaced....I am unfortunately thinking it's the water pump. I appreciate the input!

 

Anyone else??? Not looking for answers, just opinions. I would love to get this figured out so I can remove the thorn in my side.

 

Just FYI in case anyone else has this problem. It was narrowed down and solved. Turned out to be the Coolant Thermostatic Fan Switch. Replaced, and now all better...