Hi,

I am a new owner of an 1996 Audi A4 Quattro. It began to overheat last week.. and while it was very hot, the AC doesn't work (neither does the heater..) so we weren't running that.
I read up on a few of the forums - replaced the fuse to the auxiliary fan - (noticed when we were on the side of the road allowing the engine to cool that the fan hadn't come on.. ) and also the broken cap to the overflow tank. The middle section had broken off, and we were popping that in before we screwed the cap on.
My son is not mechanical, and my daughter and I were doing our best to figure this thing out.
Replaced the water with coolant, checked the oil - it's not milky..
I'm hoping it's not the thermostat, but will check the hoses driver side and passenger side if it overheats again.
This is the model that you have to remove the whole front of the car to replace the thermostat.
Any other ideas?? What should I be checking?? Thank you so much!!

 

Sorry, you post was kind of hard to follow. Did you replace the expansion tank cap or are you still using a broken / modified one?

If it's cracked / broken, the system runs under pressure and when under pressure the boiling point of the coolant is actually higher than when it isn't pressurized. If you're still using the faulty cap, that would be a great place to start.

Have you noticed any loss of coolant from your expansion tank? The fact that you indicated that you have no heat points in the direction of perhaps a nasty air pocket in the coolant system, an obstruction, or little/no flow from the coolant system's pump.

Checking the top and bottom radiator hoses is a good next step in solving your issue.