and the hits keep on comin!!!... almost makes me wanna give up

[ntrcptr]

First I noticed very low heat coming out from the vent; then while idle, the temperature gauge shot up beyond the usual "midline". Thermostat?!... hopefully? I hate loving this car.

[Bigglezworth]

If you're fluid level is full, then yes it's likely a T-stat. A swell 2-3 hours on a Saturday and you're good to go.

[4.2Crew]

.....A swell 2-3 hours on a Saturday and you're good to go.

Two to three hours for a t-stat job???... Damn, that is FAST!

[Bigglezworth]

Two to three hours for a t-stat job???... Damn, that is FAST!

Yep. A trio of timing belt changes and a rogue T-stat gone bad can quickly ensure you become efficient in doing a repair. Add another hour if you're swapping the belt, pullies, and water pump. Add another 2 hours to that if you are doing cam and crank seals.

[ttboost]

Yeah..can't imagine it taking more than 2 hours...only needs to be in service position...but I guess if you're having beer too, it could take longer...

[ntrcptr]

If you're fluid level is full, then yes it's likely a T-stat. A swell 2-3 hours on a Saturday and you're good to go.

Even at low city traffic speed the car doesn't overheat. And when it does, the fan starts up and I can smell a faint odor of burning coolant. Or maybe im just smelling things from city living. But I see no leaks on the ground.

[905084]

The green cooling temp switch?? My son's A6 did this cause the $20 tstat switch was bad....20 minutes tops if you have a High West in your hands....

[4everRS]

The green cooling temp switch?? My son's A6 did this cause the $20 tstat switch was bad....20 minutes tops if you have a High West in your hands....

That is just a sensor. It wouldn't cause the symptoms in the OP.

The tstat opens and closes mechanically, there is no switch.

[905084]

That is just a sensor. It wouldn't cause the symptoms in the OP.

The tstat opens and closes mechanically, there is no switch.

Hmm...I drove my son's A6 in stop and go traffic.....and....yes it does....and it was replaced and the problem fixed....

If the tstat is bad....temp will soar....regardless of driving conditions....

[905084]

Just sayin' try the $20 fix before you spend $500 on a tbelt, idlers, water pump, Pentofrost, and tstat.

If it doesn't overheat on the highway, it ain't the thermostat....

[4everRS]

Maybe I'm just confused on the terms we are using. Below is what I call a tstat:



This will certainly take more than 20 minutes to r&r, as the car has to go to service position to do it. The green temperature sensor is directly behind the left cylinder head, and yes, that is easy to replace.

[ttboost]

Temp sensor fixed my problem...don't recall if I had the same symptoms...
oh..and by the way, if you do replace the temp sensor, when you find it, after you drop it, tie a small wire around the clip, so you don't drop it again...

[hahnmgh63]

The Thermostat is mechanical but at idle or real low speeds there isn't enough air over the radiator to cool they system so the Temp switch turns on the cooling fans for additional air. Try to turn on you A/C (AUTO selected) and see if you hear your cooling fans come on? The larger one should come on when you select Auto I'm pretty sure, or the smaller one but nonetheless one of them should come on.
Which leads me to ask, when it was hot at an idle did you ever hear the cooling fans come on?

[hahnmgh63]

The Thermostat is mechanical but at idle or real low speeds there isn't enough air over the radiator to cool they system so the Temp switch turns on the cooling fans for additional air. Try to turn on you A/C (AUTO selected) and see if you hear your cooling fans come on? The larger one should come on when you select Auto I'm pretty sure, or the smaller one but nonetheless one of them should come on.
Which leads me to ask, when it was hot at an idle did you ever hear the cooling fans come on?

[ntrcptr]

The Thermostat is mechanical but at idle or real low speeds there isn't enough air over the radiator to cool they system so the Temp switch turns on the cooling fans for additional air. Try to turn on you A/C (AUTO selected) and see if you hear your cooling fans come on? The larger one should come on when you select Auto I'm pretty sure, or the smaller one but nonetheless one of them should come on.
Which leads me to ask, when it was hot at an idle did you ever hear the cooling fans come on?

the fans are blaring ... I didnt know i had a small one and a big one; seems like it was the big one because its loud when it comes on

[905084]

Is your system being pressurized? When you take the cap off when hot is it obvious? I've always tried to ignore the smell of antifreeze....I've always been wrong :/

[P1054]

^^ What ttboost said. If you replace the green (I've heard some older ones might be black? Mine at least was green) coolant temp sensor, when you go to put on the "c" clip that holds the sensor in place, tie a wire or piece of fishing line or something to it so if (or in my case when) you drop it down into the bowels of the engine bay, you can simply pull it back out instead of going for a very frustrating fishing expedition trying to get it back.

As far as the OP, when my sensor went bad the temp gauge just quit working randomly. Sometimes it would read correctly, then it would drop to zero. I suppose it could send a false high signal if it was going bad, but I'd be inclined to think it's a thermostat issue. Does anyone know if there is a way to check the operation of the thermostat with VCDS?

[lswing]

Good thinking, Ross-Tech a great start...hope this helps.

http://wiki.ross-tech.com/wiki/index...3/P2181/008577