Hey,
I doubt its the expansion tank to be honest, ive not seen it let any steam out etc? Its a blue one at that.
I hope it is an air block, scarily i did let the car run for about 10 mins with the cap off and was waiting for the fan to kick in...
reached dangerous temps at 140 at which i jus had to switch the car off!
I hope i can get this fixed tommorow, miss my car

Alan il try give her a proper massage yesterday and see if it kicks in..
Yeah Jay if you could pm me a number it wud me much appreciated?
p.s dont know if its worth mentioning...I put the heaters on maxand put the fan on setting 3....the air is usually hot and it was coming luke warmish?
Thanks,
G