(06-02-18, 10:56 AM)Adam2201 link Wrote: would be great if it is just a bit of rain in the sensor...
I saw loads of little tiny bubbles in the top of the rad when I started it, I only left it on for a few seconds as i didn't want it to spray out. When I've had a blown HG on a car in the past, it's been a bugger to start and drive. Also you can see the oil and coolant have mixed when you check the reservoir. Haven't got any of those symptoms so far, so fingers crossed for it being OK. I wouldn't do a head gasket replacement myself, I've never opened an engine.
It was just a thought about the head gasket. You can have a slightly leaking head gasket with only minor symptoms, but a gross leak, as you say, would cause havoc.
I once drove a Granada with a leaking head gasket for a year with no symptoms, apart from a little water loss and a slight gurgling noise from the heater. But one day it let go: the engine conked and steam billowed out from under the engine bay.
You don't seem to have a gross head gasket leak and a minor leak should not cause the engine to overheat. But hot gas entering the cooling system may trigger the warning light temperature sensor.
Of course, this is all speculation and I hope it is not the head gasket!