I just bought a 1999 A6 Avant Quattro. Everything works great except the Coolant Temp. gauge does register until I am sitting at idle (but not always). It will move 1/4 to 1/2 up the dial but as soon as I start moving, it slowly moves back down to cold. Any thoughts on this? All of the other gauges work just fine and none of them are registering excessive heat, etc. so I am assuming the temp. is within normal levels!
Thanks,
Greg

 

not a problem if the cooling fans cut in the gauge is just a guide like most other gauges

 

Are you sure your thermostat is working? My temp gauge is stable, all my european cars have been that way. When I come to a stop light, the gauge stays still. If the car does start to get too warm, the fan will turn on, but the gauge doesn't really move that much.

When you say when you take off the gauge moves back to cold, do you mean it goes all the way to the left? It is normal for a temp gauge to fluctuate while driving. Especially in the hot, while in bumper to bumper traffic with the AC on, but even then it should not move all that much. But what you seem to be describing does not sound normal to me. I think your thermostat is sticking open. Do you have heat while sitting at the red light, but then loose most of that head while driving down the highway? I sure hope I am wrong.

Jeff

 

Hi Jeff,
Everything seems to work normally. The climate control works great in any condition, heat, A/C etc. all work fine. During normal use, even on a 700 mile trip, all other gauges appeared normal, the oil temp was on the low end, etc. but the coolant gauge never moved. We pulled off the highway once, stopped at a light,and drove a bit at a mall and the gauge moved up to the center of the dial. Once we started back on the highway, the gauge went all the way back to the left. The fans seems to work fine and there is absolutely no indication of overheating. I even opened the hood when we stopped for gas and there was no excessive heat or anything under the hood. Perplexing!
Thanks,
Greg

 

I am sorry to have to tell you this but your thermostat is stuck open. You are exibiting classic symptoms of a stuck thermostat. The good news is it is stuck open (car never warms up) instead of stuck shut (car overheats). The bad news is you own an Audi, and Audi probably is the single most expensive car to replace a thermostat on. Call your local indy mechanic, tell them what you just told me in the previous post. Again I am deeply sorry. Audis are good cars, don't let this turn you off to Audis forever.

Jeff

 

Why are they so expensive then.......................Because i think mine is stuck open as well

 

Thanks Jeff,
I kind of thought that might be the case. There are a couple of service places here in D.C. that are supposed to be very good and pretty reasonable for VW's and Audis. I used to have an 89 MB 560sl so I am already somewhat accustomed to the price of "maintenance" on geman cars! I have had the car for a couple of weeks and love it! It looks very similar to yours only it is Green with Tan interior. Runs and drives like a dream! Now, if I can just find a retractable cargo cover, life will be perfect!!
Greg

 

Its expensive because of the labor involved in replacement. You have to remove the timing belt to get to it.