My car keeps overheating - what's the problem?

Recently, I had the water pump changed in my 2005 SEAT Ibiza. It was always at 90 on my temp gauge, but since the pump change it keeps overheating. It's not the coolant as I've topped it up and there are no leaks. Also my heaters are not blowing hot, is this an air lock problem or thermostat problem?

Asked on 31 December 2017 by Terry Graham

Answered by Alan Ross
Well firstly eliminate the air lock by removing the filler cap from the expansion tank and run the engine (also squeeze the coolant hoses making sure of any moving parts). If you have any air in the system, it should show as bubbles in the expansion tank. If your engine is overheating (going into the red) within the first 15 mins of the engine running then I would suspect the thermostat. The other thing to check would be the heater control valve, in relation to the overheating and also the lack of heat in the car.
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