overheating and other issues

[jasst]

My 2006 2.0 fsi est was overheating when stuck in traffic, I have replaced the water pump, both thermostats and both temp senders, before I did this work it struggled to get to full temp, which it now does, and runs at an indicated 90 degrees until I get stuck in traffic, when it rises to 110+ and I have to put the heater on max to bring it back down, what should I look for next?
Also have another issue, when I did the timing belt the other day, the battery was disconnected for about 10 days, since reconnecting it will not store my average fuel consumption, and every time I switch engine off, it starts at Zero again, and there is no option 2 on the mfd to display average mpg.

[jmurray01]

Have you checked that the radiator fan is cutting in when it gets to/exceeds 90 degrees? Sounds as if it isn't running which will cause it to overheat unless you put the heater on.

[Crasher]

If it is showing 110 on the gauge it is a LOT hotter in reality. A few days ago I was monitoring a VAG cars warm up and I got the feeling it was getting hot but the gauge said 90.... when I checked in the measuring blocks it was 108 so I turned it off. The main cooling fan, which contains the controller, had failed.

[jasst]

When I did the thermostats I ran it up, and tried various things like air con on or off, sometimes the fans would run sometimes not, is there any way of testing the fan controller/

[jmurray01]

The fan should always run with the A/C on so don't let that fool you into thinking it is running under normal conditions. What I would do is take it for a drive then park up so as to provoke an overheat situation and see if the fan is running without the A/C on.

[jasst]

When I tested it, sometimes the fan would not run even with the air con on.
When it got hot in traffic again on sat I parked up and lifted the bonnet to check, and the fan was not running.
Another thing, just been looking at new fan units on the likes of *******, have got what I think is the correct part no, but even then there seem to be different power outputs even for the same part no! (confused)

[jmurray01]

Nothing is simple on these cars is it!

You could say that!!

[jasst]

Interestingly I was looking at the handbook for an entirely unrelated reason and I read the page regarding the gauges, apparently the normal operating range is up to 120degC, and the warning light will not come on till that temp is exceeded, so I may have been panicking for nothing! still seems to be a very high temp for the engine to be running at, but what do I know!

[jmurray01]

Interestingly I was looking at the handbook for an entirely unrelated reason and I read the page regarding the gauges, apparently the normal operating range is up to 120degC, and the warning light will not come on till that temp is exceeded, so I may have been panicking for nothing! still seems to be a very high temp for the engine to be running at, but what do I know!

Yes mine says that as well, but 120°C is definitely not normal unless you are towing a caravan up a steep hill in the hottest place on earth!

In the UK a car should never exceed 90 maybe going up to 100 tops if you're pushing it.