Hi all,
I am back with some more and I am hoping that someone can shed some light:
1. My sniff tester has finally arrived. I have done the test 4 times and the magic liquid has not changed colour. I have done it when cold, when warm and after taking the car for a short drive and back. There appears to be some fluctuation caused by the air stirring when revving the car but other than that nothing.
2. If I leave the car idling for long enough the coolant will overflow the tank, cap on or off makes no difference. The radiator hoses will begin to harden but not rock hard or buldging.
3. While testing, I noticed that the fan will never kick in. I've done the output test with VCDS and the fans will turn on at all speeds.
4. I have unplugged the coolant temp sensor at the bottom radiator hose so that the fan will stay on continuously. I then left the car idling for about 30 minutes with the coolant cap on and the level remained within limits without overflowing.
5. Can anyone suggest a set of observations in VCDS to help me troubleshoot this? What are the measuring blocks for the temperature and at which point should the fan kick in and what is the telltale block?
Bonus picture:
View attachment 104744