Cooling water always goes ++90° (urs4)

[MattP]

I have the car now since a a good month and i noticed the cooling water is mostly close to 100°....
This night i drove 60km it was just on 90° then i drive in town for 10km with 5-6 times a hard rev in 1 or2nd gear to max 5000rpm and there it goes up to 100°.
On the way back it didn't move any more on the highway i did a few pulls in higher gears and no movement. When i was home 3 times in 2nd to 4500rpm and i thought it went up a very little bit again.

Also when i towed a trailer with 1700kg the water and oill where both pretty hot, but water never went above 100.

Few days ago



This night




I recon there is some kind of a problem
-Water pump doesn't work 100% (previous owner told me he replaced it 20 000km ago)
-The engine needs 5/700ml oil every 1500~2000km
-Other common problems on the S4?

My Rs2 always stay at around 80° even after 1000km road trip.

[Majorcina]

He is burning a lot of oil if i recon good

[MattP]

He is burning a lot of oil if i recon good

Indeed but that not really a big problem for me just adding a bit and good to go but the water is a bigger issue for me.
I just wrote about the oil maybe it has something to do with the high water temp...

[UrS4boy]

C4 UrS Thermostat Info

I have the car now since a a good month and i noticed the cooling water is mostly close to 100°.

I'm not saying you shouldn't flush your radiator out sometime soon but I do think you are panicking a little pre-maturely. In the photos you have provided, I see 95 C in one and maybe 98 C in the other. Nothing over 100 C. Nothing to freak out over. Especially since the trailer towing did make the temps rise very much

You might want to read this:

http://forums.quattroworld.com/s4s6/msgs/21881.phtml

[MattP]

I'm not saying you shouldn't flush your radiator out sometime soon but I do think you are panicking a little pre-maturely. In the photos you have provided, I see 95 C in one and maybe 98 C in the other. Nothing over 100 C. Nothing to freak out over. Especially since the trailer towing did make the temps rise very much

Maybe i give that a try I just want a car without any problems when i do a long road trip. (if i do 5000km in 15days i don't want to strand somewhere in the middle of Norway with overheated engine or so)

Also where could i start the search that it drinks quite a bit of oil?

[JariP]

I had this kind of readings with a new aftermarket temp sensor. For the first year after fitting the sensor. Then something happened and now it shows max 80°C. Real world temps are where they should be, around 90°C. If you have an infrared temp gauge, see what kind of temperatures it shows for example from the hose going from cylinder head to heater matrix.

[vidar skotheim]

If you strand in the middel of Norway i can help you

[MattP]

Now the weather is pretty hot here and in traffic jam(3/4min) it goes from 95 to 100/102° witch is pretty fast, so if wondering if i am in a big one...
If you sit in the car the fan on the left is turning, the right one not.
No leaks on first sight as coolant stays on the same level.

What should i be checking
-Thermostat
-Radiator flow through?
-...

[domas]

What is the temp in suburban driving, highway lets say?

[UrS4boy]

AAN Thermostat info including replacement DIY

What should i be checking
-Thermostat
-Radiator flow through?
-...

I think your thermostat is fine but for peace of mind, you might want to replace it (could be sticking partly closed).

Other suspects are:

1. Water pump
2. Clogged radiator

AAN Thermostat DIY is in this post:

http://forums.quattroworld.com/s4s6/msgs/21881.phtml

[MattP]

What is the temp in suburban driving, highway lets say?

94°~98°

[domas]

it seems that the system functions okay, BUT it is a little inefficient. Rad flush is my guess.