hi, ive just bought a fiesta zetec mk5. and it constantly over heats, to start with if i put the heating on in the car it wud drop the engine temp, so i took it to a ford garage told them the problem and they said they sorted it but im now having to go bak for a 3d time because it keeps over heating, theyve changed the thermostat cleaned all the coolant pipes including rad, and changed the sensor, and its still doing it, was wondering if any1 had any ideas because obviously this ford garage dont know what there doin. thanks for replyin.

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