tylerm99

I noticed that according to my Scangauge II that my water temp is always around 100 degrees. The dash gauge says 90. I don't overheat and the water pump was replaced less than 15kms ago.

Is that "normal" operating temp range for my car or should it be lower?

Phase

it should hold 90~92, but with inferno days like today (traffic, AC on, etc) may get to a 100, but not over. trust your dash gauge.

tylerm99

The reason I ask is the Scangauge reads right from the computer so that is what temp the sensor is sending out. I know I am in the safe range but it holds that temp even in cooler temps and down the highway with lots of airflow\low rpms.

hoeser

I would suggest the exact opposite. The ScanGauge is pulling the data from the ODB-II bus and it's going to have the most accurate data. (short of hooking up a VAG-Com that is) - The gauge in the cluster is more of an idiot light than anything - it will read 90 anywhere between like 80 and 110 - it is like this in most VAG vehicles.

100c is a little hotter than what I would expect but it's still within tolerance. What did it read before the water pump was changed? Thermostat was probably changed at the same time and is likely opening later than the last one. For reference, beating the **** out of my 07 3.2 quattro this week in the hot weather I've seen between 94 and 96c on my scangauge.

tylerm99

No idea, I got the scangauge for my birthday (what a great wife!!!) after the pump and t-stat was changed. I'm pretty sure it is OK but wanted an idea of what other people are running.

hoeser

if its a little higher than usual for an 04 1.8T it's probably simply because the thermostat opens just a bit later. I wouldn't worry about it until over 105.

adamstasiak

No it should be 90 and during hot days 88 or 87.
There is no way for it to be at 100 unless you added some Radiator stop leak fluid or some conditioner to your coolant.

Have you added some other coolant from the gas station that is not AUDI approved?
Your system is plugged by something.
What is your oil temp?

If the oil is at 100 there is nothing to worry about.

Phase

I bought this vehicle with 200k on it so I don't know if previous owner did anything to it. I was sitting in a traffic the other day it was +38 and my needle climbed to almost a 100 ~98. Both fans worked I checked it later. So I thought maybe it just was too hot or maybe thermostat is going. And then after few days it climbed to almost 110. That was serious. Then temperature droped back to 98 ~ 94. I came home pulled the inlet hose off of the heater core pipe and noticed that I had extremely weak flow from it. Temp was still at 90 and not rising. It was ok for two days after and on third my wife told me that it went on 95 again but not higher. As I said I don't know what 's been done to this car before but I decided not to gamble with it and this saturday I' m doing w/pump, t/belt, t/stat. Cause chances are it hasn't been done at all

adamstasiak

No they do not have thermostat problems.Take a look at the top up tank. Is the fluid clear? If not you just need a flush.

adamstasiak

Ok I thought about it.
The guy added radiator stop leak and now the whole mess is plugging your system. You will have no heat inside during winter. You need rad flush and you need to fix the leak that the seller tried to hide from you.