Thermostat malfunctions (Mondeo 2)

Thermostat does not open

Cause: the valve plate is jammed or "stuck".

Signs: the temperature indicator is already beyond the red mark, but the radiator is still cold to the touch.

Possible consequences: Driving with a closed thermostat can cause severe engine damage. The cylinder head gasket may burn out, the cylinder head may become warped or cracked

Method of elimination: Wait until the engine has cooled down, unscrew the thermostat housing fastener and remove the thermostat. Driving without a thermostat for a while will not harm your engine.

The thermostat does not close completely

Cause: a foreign object has entered the thermostat.

Signs: after starting a cold engine, the radiator immediately becomes as warm as, for example, the thermostat housing. The car interior heats up slowly.

Possible consequences: If the engine does not reach operating temperature, wear on its parts increases.

Method of elimination: Replace the thermostat.