1.6 156 overheating
Got a 1.6 156 about a 3 weeks ago and immediately changed thermostat as it was stuck open. Now I think I made a bit of a mistake with the gasket sealant as there was a small leak around the housing. The car was running fine and heating and cooling as it should but using a lot of coolant but I just kept topping up with water as I knew I'd be sorting it soon. This was on the to do list for this weekend (remove, reseal and refit the stat).
This week though, things changed in that the car began to run very hot (not quite overheat to the point the red light came on, but getting there). The stat would only seem to open if I floored it which seemed a bit odd, and the coolant was no longer being leaked. Also, as the car heats up (even past where the stat should open) the hot air blower only blows cold, but when the stat opens and allows the engine to cool, the air gets hot. It then steadily cools until the engine temp is way up and its blowing cold air again. Its at this point that I'm stuck in traffic, allowing a big enough gap open up so I can floor it in first to try and somehow force the stat open. (I must look like a right knob!) I've tried just revving at a standstill but that doesn't have any effect.
At the moment I'm hoping that the re-sealing of the thermostat and a flush and bleed of the cooling circuit will sort me out, but I'm afraid it might also be something like a water pump failure? Anyone got any ideas?