My car doesn't get up to normal operating temperatures sometimes, (sometimes it does). It never overheats.. Also the heat seems to only work when driving. I got 114k on it. I had the timing belt replaced around 108k and I believe they did the thermostat with it cause if I'm not mistaken it's usually done at that time cause it's in a bad location right? Any ideas what the issues is? Thanks for your time.

 

Forgot to add it's an 2001 Audi s4. Also coolant levels are good...

 

Thats how mine is. I'll go out early to start the car and let it warm up. I've gone out as early as 15 minutes before I've had to leave, still wouldn't warm up (on the gauges) until after a couple minutes of driving. I've got a 2000 S4

 

Sometimes I can be driving for an hour and it still doesn't move...

 

You got me beat there. Mine doesn't do that. That would prolly be a sensor problem. One way to test that would be drive it for a while , like a good 20 or 30 minutes. If the gauge hasn't moved, stop and see if the coolant hoses are warm or if the coolant itself is hot. If the actual fluids themselves haven't gone up in warmth, you could have some serious problems.

 

When I leave classes tonight I'll check that. I'm prety sure Rhe hoses get warm. I really hope it's nothing serious, I have put over 2k in this bad boy in the last few months and it's killing me considering I'm in school.

 

I agree it is good to replace the coolant sensor for starters. Just had mine replaced on 2000 A6 Quattro.

 

It is the coolant temp sensor.. It seems there are two circuits in it. One that the ECU uses and the other is for the dash gauge. My A8 ran fine but the temp gauge was dead for a while. Finally it started not wanting to fire up and run when warm. Hooked up my Code Reader that will also read the data from the ECU in real time. Noticed the coolant temp dropped a 120F in about 2 seconds while monitoring it one day. Replaced the sensor (took 10 minutes and be sure to get a new plastic retainer clip as they get brittle and will probably break when you remove it) and all has been fine since. Dash gauge works perfectly too.

 

I have a posting of a similar theme. Based on my recent experience on our 2000 Audi A6 Quattro, we had a code that had come up several times related to temperature. Brought the car in to our local shop that specializes in German cars and based on the code and based on the scanner they hooked up to our car, they could see our coolant temperature sensor was not reading correctly and they replaced it. The part on the 2000 Audi A6 Quattro is not that difficult to get to and replace.

The labor and part price for coolant temperature sensor replacement is reasonable so it may make sense to have that tested first.

However, on our A6, if there is an issue with the thermostat itself, different story. More Labor [similar to that involved when changing a timing belt] is required because many parts need to be moved from the front end to get access to the thermostat which is an inexpensive part but the labor can turn into 5 hours.