hi,
i have a 2000 audi a8 the car runs fine with the a/c on but as soon as i stop somewhere and keep the motor running the temp gauge starts to climb and the a/c starts blowing hotter rather than cold. but if i stop and keep the car running and turn off the a/c it will not over heat maybe i need a fan but which one? please help

 

Im having the exact same problem on the same car,same year. i was wondering if you found any solution.i bought more coolant (G12) and added it but to no avail.

 

I had this exact problem on my VW Passat, turned out to be the waterpump (plastic implellar had failed portions), with the A/C on in traffic the car would begin to overheat, a relay turned off the A/C to keep the car from overheating. When you started moving again the air would come on cold. Check the coolent flow from water pump, and or possible obstructions in radiator.

 

Also make sure your fans are both running when a/c is on...smg

 

thanks for the reply il check it out and see if it helps

 

Thermostat?

 

Check the water pump 2nd first check the viscous fan coupling with a carrot or similar at engine opperating temperature. If it stops by applying a carrot or pencil then that's the cause then pump is a larhe job as the whole front end of the car has to come off as if you were doing a timing belt change.

 

Hello to all of you that have posted.

I had the exact same problem with my '00 A8 and it got to the point where my a8 would heat to the highest point when i was on the road saturday morning. what you'll have to end up doing is you will need to replace the thermost and the gasket leading from the t-stat to the lines. the rise in heat is usually due to a blockage in the t-stat or somewhere along the lines. tends to come with age cause my car only has 59k miles on it, but before i got it, it had been sitting for a substantial amount of time so im assuming the t-stat and gasket just need replacement over time on other A8s..(not sure). but yea, i had to stop the car and the y-pipe in the lines carrying the anti-freeze exploded due to the blockage in the fluid. the anti-freeze sprayed to the top of the engine block which emitted steam from under the hood.

so yea... long story short... it's 6 hours of labor because it requires removal of the entire front end which translates into $450 in labor and $125 in parts... but yea, it has to be done or else it'll lead to your entire engine seizing due to heat i'd think.