third thermostat in 2 years any help would be great

[keithla4]

like the tittle says i have replaced my t stat two times and now going on the third one it keeps sticking open has this happened to anyone else in here im getting tierd of changing it and i have replaced the ECT everytime i change the t stat and i just changed it agian this morning and it didnt fix it the stat is stuck open im getting really pissed off and every stat is from audi direct help me figgure this out

[HTA A4]

Only on my second one but it was messy when I had to replace it. The seal broke on the thermostat causing a MAJOR coolant leak. So make sure you keep replacing them if they are getting stuck open.

[cjonesgo]

Sounds abnormal. Are you using g12 coolant? Not mixing or topping off with other types? Mixing = bad.
buying OEM t-stat or aftermarket? I assume there is an aftermarket. Try another brand.

This is all I can think of.

[keithla4]

yea i am using g12 coolant and the t stat and ect are both oe from audi parts

[dougyfresh]

Have you inspected the wire going to the thermostat? That is for the heating element within the thermostat. The thermostat is MAP controlled based upon inputs from the other coolant sensors. As those sensors provide data to the ECU the ECU then sends a voltage to the heating element to adjust the thermostatically controlled springs (heat changible springs) within the thermostat to regulate coolant flow.

What I am getting at is, perhaps, the wire has a short causing the thermostat to always be open. If that is the case, your thermostats are OK but your wiring harness needs attention.

1) check continuity on that wire from somewhere upstream to the connector on the thermostat
2) check resistance on that wire. What is an acceptable value? I do not know.

[MikTip]

1.8T or 3.0L engine?

[fitch303]

I'm going through the same thing right now. It used to warm up slightly between cold and middle but now the fans turn on after startup and I never am above cold. The audi connection said I need a new tstat

[kovalevandrew]

Trust me, i know ALL about those bastard thermostats. Been through 5 of them in the two years... Ever since i change to a new dealership after moving house.

The new one was screwing me with the replacing of coolant. One bottle of the G12, and not the G12 Plus, and the rest water.

So after getting a lecture(for over 2 hours) from a guy who was at a friends place when i was there for a party. He does all the servicing on the S/RS models only at one of the bigger dealerships here.

To cut a very long and drunken story short... G12 Plus, and ONLY G12 Plus goes into your car as coolant, not a drop of anything else, heaven forbid water.

Since doing that, no thermostats getting stuck open, no overheating, no coolant spraying out all over the place after driving the car hard, and i drill my car.

[dougyfresh]

I run about 90% water and 10% G12

no problems here.

sometimes I run up to 99% water.

[kovalevandrew]

When engine code you running...?
APU is mine. I know they fixed a lot from the motors in the B5 to the B6.
I run mine hard to well over 7500rpm everyday. If i put any water in, cooling system as a hissy fit.

[dougyfresh]

It was AMB (1.8T for the B6 in North America)

Now I have a built 2.0L stroker using an AMU block but with my AMB thermostat and external accessories.

[kovalevandrew]

Wow, nice. What figures you getting from it...?

Mine is a 2001.5 B5. Was literally the last B5 1.8T sold in SA. No stock 2.0T comes even close, they simply too slow. The new S3's have me on launch, half way through third i go flying past them. Not bad for a car with over 210 000km on it...

I know a lot of people here have problems with their coolant systems. Running only G12 is the only thing that works.

[keithla4]

so what your saying is not water just g12 plus i have never heard of that ever and i read up on the t stats on our cars by the way it is a 1.8t AMB and know i know why the damn things are so much money well im going to change it agian and try running straight g12 plus i hope it works this time any ways i wanted to pull my intake manifold and powdercoat it

[dougyfresh]

Wow, nice. What figures you getting from it...?

Mine is a 2001.5 B5. Was literally the last B5 1.8T sold in SA. No stock 2.0T comes even close, they simply too slow. The new S3's have me on launch, half way through third i go flying past them. Not bad for a car with over 210 000km on it...

I know a lot of people here have problems with their coolant systems. Running only G12 is the only thing that works.

It is still getting tuned. I'll have numbers once its tuned.

[AudiTechS4]

hmm i work at a dealer and its a 50/50 mix of g2 and water on every car even the rs4 and rs6's

[AudiA4_20T]

Wow, nice. What figures you getting from it...

Ya where are they at?