Hi all, Long time lurker (due to many, many various problems), but 1st time poster, due to what seems to be a bit of a strange one. A bit of background - a couple of weeks back, my A3 1.8 (non-turbo) started seriously overheating, to the point where the warning light came on. Got it booked in - the plastic water pump impellor had gone. New Rad, water Pump, timing belt and radiator and it seemed to be okay. Driving into work yester, which is a longer journey than house to garage, I noticed the temp starting to increase past 90 again. Obviously my heart sank - £357 for a non fix hurts quite a bit. However, it got halfway between the 90 and 100 marks then started coming back down, then went back up, then back down and so on. Looking through the forum, I found out about the Climate Control display trick and how the display sometimes doesn't match the dash guage. Reading up, it seems the normal behaviour for the gauge is to stay at 90, while the Climate control display can go up to 104 or so. This doesn't seem to be happening to me. The guage and the temp gauge are perfectly matched - goes up to 104, fans seem to kick in, drops to 98-100, rises, fans kick in, repeat. Do you know what would cause this? Faulty Temp sender? (wasn't replaced, although just over a year old). The thermostat is new - maybe a faulty or sticking one? Many thanks.