2000 S4 Thermostat Question

**jacksontop** · 01-13-2009 03:24 PM

I have a 2000 S4 with 58 K on it. The temp guage inside the car was acting up.

The gauge is intermittenly working. After the car warms up the temp gauge will not move half of the time. I can drive the car for an hour and the gauge may come to normal range for a bit, but will eventually drop down to nothing after time.

Other times it will come up to normal operating range and work properly.
The car heats up normally, as the heater is working properly.

I have been taking this to a local independent VW/AUDI mech. and he replaced the sensor under the hood.

Well the wife drives this car, so I am not 100% certain if the problem was resolved after replacing the sensor. Recently (6 months after sensor was replaced) I drove the car and noticed the temp guage doing the same thing. We called the independent mech. who told me that most likely the thermostat is bad, since we replaced the sensor.

I took the car to the local AUDI Dealer in town and they are telling me that the thermostat is most likely bad. When they go bad they stay "open" is what he is telling me. I need to replace the thermostat and to do so it will take 10 hours of labor at $110/hr plus the parts. The service manager is telling me to replace the timing belt also while we do this. They want over $2600 to replace these items.

I want an honest opininon from some AUDI fanatics on what to do. Does this sound like the t-stat is bad or did the sensor go bad again. The independent mech. told me the sensors go bad frequently on the VW's they work on.

Any help would be greatly appreciated.

**infinkc** · 01-13-2009 03:30 PM

well a new sensor is fairly cheap and a very easy diy. If you are at 58k i would just go do the tb/wp now. 2600 is way too much for the job.

**gointoscott** · 01-13-2009 03:32 PM

The sensor is very easy to replace. Cheap too, I would try that first and see if it fixes it.

About the timing belt, has it ever been replaced? The book says 90k I believe. But most recommend doing it earlier. Dont want it to break and bend some valves or hurt a piston or two.

$2600 to do timing belt job is outragous. I had mind done and cost me 800-900 something like that. Check around and you can find a audi independant place to do it way cheaper then what you were quoted.

**ThirdStrike** · 01-13-2009 03:32 PM

t-stats going bad in an open position is 50/50. they can also be stuck closed. anyways to see if its stuck open start the car from dead cold (after its been sitting for 6+) hours and see if you have coolant running through the lines.
as far as your labor and work...to replace the thermostat u do have to go pretty deep in the front end. do you need to do a timing belt in the same job? no. since you have everything apart u might as well tho.

**s42k5b** · 01-13-2009 03:48 PM

wow. That is extremely expensive, to bad you dont live in NY. Why dont take the car to the independent audi volks mechanic you were talking about?

**stapo69** · 01-18-2009 05:30 AM

I just replaced my thermostat yesterday, I do have a copy of the workshop manual which helped greatly, a long job, took most of the day cos so much has to come off the car, but not particularly difficult, replaced waterpump while I was in there too, and all belts make sense too. Depending on how spanner friendly you are it's worth giving it a go I'd say, def prefer a long day in the garage than paying thousands for a $20 part. It's the labour that costs so much cos it's a time consuming job believe me.

**MacDaddy** · 01-18-2009 02:46 PM

Originally Posted by infinkc

well a new sensor is fairly cheap and a very easy diy. If you are at 58k i would just go do the tb/wp now. 2600 is way too much for the job.

I agree, your car has next to no millage and your tensioners and idlers for the timing belt will be just fine.

I don't know why a dealer would take 10 hours to do that job, with the proper tools and working in a shop i would give myself 5 hours and thats being generous.