hey guys, tonight my car has started playing up, the temperature has started to shoot up and the revs and idling well too high , just above 2 thousands revs. These stick on unless i put the clutch in and drive , there is still water in my radiator, but there was vapour coming out of the little shoot on the expansion tank saying min and max. any ideas ? do i need a fan on my rad? or is it the sensor? has this happened to anyone else ?