Left passenger window open during a storm, very wet inside :(

Following on from my thread about water under the carpets What's under the carpet in a 1996 A4? , I have now noticed that the display for the aircon is going a bit bonkers.

Some LEDs fail to light up, especially for the fan speed, and generally behave in an arbitrary way, but the system seems to work OK if I ignore the display and just put it in "AUTO".

However, when I do this, the aircon compressor clutch engages (I can hear it click), even now when the ambient temperature is about 6ºC, so I have to push the aircon button to disengege it.

I move the car out of the garage into the sun every day to dry it out (when there is any sun), and today noticed that the electric cooling fan was running continuously after I started the engine.
It stopped after a while, and I am wondering if it starts when the aircon is switched on, but has time delay before it stops, as maybe I hade been playing with the aircon control panel just after starting.

I also noticed that after the cold weather began recently, the temperature gauge only reaches 70º, whereas before it always sat steadily on 90º. This happened before the rain soaked the dashboard, so I don't think it's connected with that.

I assume the thermostat is stuck open and have bought a new one, but don't fancy crawling under the car in this cold weather. Could someone confirm that the temp gauge should normally sit on 90º, please?

Well, I decided to replace the thermostat, so drained the coolant by taking off the hose connected to the thermostat cover.

Managed to catch most of the expensive new coolant I recently put in - whatever didn't go down my sleeve, and after prising out the O-ring the thermostat fell out.

NOW - how do I hold the new thermostat and O-ring in place while I replace the cover, please?

Someone must have a tip for this, I don't want to go through all the performance to take out the thermostat/water pump assembly just to turn it upside down!

The old thermostat tested OK when heated in a pan of water. Started to open at 87º, full open by 90º or so, and closed correctly as the water cooled down.

I have ordered a new temperature sensor to fit if the gauge still reads low. If that doesn't do the trick I'll just leave it as is for now.


Re. the electric cooling fan, I now realise it runs a while after the aircon is switched off.