mannya4

Dealer says no fault code, no go...

here is what they wrote:

35391 Scanned for faults and no faults were found relating to this issue. This vehicle will be scanned upon return of the road test and checked for faults again. The vehicle's coolant reservoir shows signs of overheating due to the crusty residue of an overflow, as well as the customer's complaint of doing so. No faults were found after the road test, if this issue occurs again, then diagnosis will be necessary at the time of complaint.

Mike_L

What car are we talking about here?

snagitseven

I think MannyA4 posted this in the wrong forum. 97 1.8tqms?

Mike_L

Yeah, thats why I was asking.

Brooklyn

Does the A6 use the same thermostat as the S4? The tstat in my B8 S4 crapped out on me at 52k. Symptoms included engine fan running constantly followed by erratic swings of the temp gauge and the car thinking it was overheating as a result.

mannya4

I have a 2012 A6 P+...have not replaced my signature because I still have the A4...sorry for the confusion...

Brooklyn

No confusion brother - you're having this problem with your A6, right? I'm asking whether the A6 uses the same thermostat as the A4/S4 because the symptoms you described are identical to what I experienced when the tstat in my S4 died. I was hoping the A6 used a different thermostat all together, because otherwise it's entirely possible the A6 could experience the same failure.

mannya4

So the symptoms were the same?

Brooklyn

Very similar. I first noticed the engine fan wasn't going off one day. Brought it in to the dealer and they told me they couldn't get to it for a week but that as long as the needle wasn't rising, iit should be ok. A few days later almost 60 miles from home, the needle started fluctuating rapidly. Inching up to redline then dropping back down to normal. Heading back home it finally started redlining. Pulling over would result in the needle dropping back down but once I got going again rapid swings by the needle. Most annoying 60-mile drive ever. Dealer replaced the tstat and that took care of it. One difference though...no signs of coolant overflow. Early in the life of the car though I complained of massive coolant loss with no sign of a leak. Those multiple complaints early on resulted in them replacing my tstat for free despite having about 52k on the odo when it failed. If the A6 uses the same tstat, it's not a matter of if, but when it will fail.

jr'sAudiA6

I thought I would add to this thread a recent experience. While driving back from Pahrump Nevada this past Sunday my wife and I noticed that the AC was not putting out cool air. After adjusting the temp and getting no change I look at my instrument cluster and the temp gauge is about 3 bars above the normal range and a few miles later it moves into the red and I get a warning to stop the car and let the engine run to cool it down. I do find a safe place to pull off and let the engine run for a few minutes but eventually turn it off. May be 10 minutes go by the temp is back to the normal point. Continue on going up a slight grade and it overheats again. Pull of at a safe point and wait again for it to cool down. Only need to go about 15 miles to service station. Once it is cooled down we take off again but this time the drive is primarily down hill to the service station so I can get some gas. Make it with out the temp gauge moving above the normal range. Put some gas in the car and take off again, ever so slightly up hill. Make it about 1/2 mile before it overheats again so I turn around and return to the service station only this time because I did not stop as soon as before I loose some cooling fluid from the expansion tank. I wont bore you with the story of having to get it towed home which was 216 miles, the failure occurred in an area where there is no cell coverage so really happy I was able to get to the service station. Anyway took it to the dealer today and they are replacing both the water pump and thermostat.

I have 41470 miles on the car and it has been rock solid for the 2.5 years I've owned it. Hopefully this is one time event for this car.