Working temperature on 2.0 TDIe during winter time

**Novica** · 13-01-2016,09:45 PM

Hello,

I need urgent reply as I will do timing belt service on this Friday and if I have to change thermostat that is good moment to do it.

As I have bought my car this summer and it is first winter that I am driving it on low temperatures, I have noticed that if I am driving it downhill with low RPM (arnd 1500rpm) the temp gauge needle going slowly down from 90 to lets say 80-75 (little above middle line which is between 50 and 90). Outside temperature is +5 degrees C and internal (cabin) heating is on and set on 23 degrees C. As soon as I start adding throttle on even road or uphill temperature is going to 90 and never pass above 90. The car is getting fast 90 if cabin heating is off, also is getting 90 even if cabin heating is on when i am going outside the town in this winter time. During summer time the temp gauge nedle was always on 90 and never fluctuate. This is first time that I see that she is moving below 90 on this winter time (mostly on temperatures which are below +10 degrees C).

The car is Audi A6 C6 model, CY 01/2011 year, 2.0 TDIe 100kw, 180000km on clock, sedan.

I am asking if somebody who has same car notice similar behavior or the temp gauge needle is fixed all the time on 90 regardless outside temperature?

Thanks for fast replay, I appreciate it.

Kind regards

Novak

**Guest 2** · 13-01-2016,09:48 PM

correct, what you're seeing is normal for cold temps.

**Novica** · 13-01-2016,10:02 PM

Originally Posted by Chris

correct, what you're seeing is normal for cold temps.

Many thanks Chris for your fast reply.

As I have driven A4 B6 1.9 tdi 2004, the needle was fix all the time. Even when temperature was going on 80 degrees C or up to 100 (monitored on Vag Com) the needle was showing always 90 regardless outside temperature. But when I get failure of thermostat during summer time (when outside temperature is around 30 degress) the needle was going down on downhill road up to 70 degrees.

The story here is different, but I was a little surprised when I saw small fluctuation of temp gauge needle. If it is happening to you guys as well then I will not change thermostat. Suppose that it is working properly.

**Guest 2** · 13-01-2016,10:05 PM

Happens both on my 2009 A3 and 2015 A4, moreso if you're sucking the heat out of the system with the heater.

**royclark** · 13-01-2016,10:09 PM

90 is your thermostat setting. This is the correct operating temperature for your engine.

**Novica** · 13-01-2016,10:09 PM

Originally Posted by Chris

Happens both on my 2009 A3 and 2015 A4, moreso if you're sucking the heat out of the system with the heater.

Thanks Chris, that is enough for me. So this is normal behavior and I will not touch thermostat. I suppose that if thermostat is always open engine will never get 90 degrees.

Regards

Novak

**Novica** · 13-01-2016,10:10 PM

Thanks Royclark,

I am happy to hear that

**Novica** · 14-01-2016,08:28 AM

Good morning to All,

Just for information, I have checked time and distance this morning as soon as car get 90 degrees from cold engine.

Outside temperature was +4 degrees, cabin heating switched off. Car was driven inside town with average speed 45 km/h, passed 7,6 km in 10 minutes, driving RPM from 1500 - max 2200(on changing gear), mostly flat road and after that temperature gauge needle hit 90 degrees. Then continuing driving few more 100-300 meters, temp gauge needle was going up and down, approximately 1-2 milimeters below 90 degrees all depending if the car is under loading or coasting without throttle. When I reach destination after 8.4 km and 11 minutes the needle was at 90 degrees and stay on it until I parked the car. All the time cabin heating was off.

**royclark** · 14-01-2016,11:52 AM

Originally Posted by Novica

Good morning to All,

Just for information, I have checked time and distance this morning as soon as car get 90 degrees from cold engine.

Outside temperature was +4 degrees, cabin heating switched off. Car was driven inside town with average speed 45 km/h, passed 7,6 km in 10 minutes, driving RPM from 1500 - max 2200(on changing gear), mostly flat road and after that temperature gauge needle hit 90 degrees. Then continuing driving few more 100-300 meters, temp gauge needle was going up and down, approximately 1-2 milimeters below 90 degrees all depending if the car is under loading or coasting without throttle. When I reach destination after 8.4 km and 11 minutes the needle was at 90 degrees and stay on it until I parked the car. All the time cabin heating was off.

Looks to be working OK.