Hi there, my first reaction was to replace the thermostat as this is a cheap item to change but i cannot seem to locate the thermostat, its not where i would expect it to be. It is a 2005 1.6 zetec focus. Also i am not entirely convinced the car is actually overheating, the gauge is jumping about in large leaps going from the normal mid position right to the top in one swift movement, if i stop the car and turn off the ignition then back on sometimes the gauge is back to the mid position but not always. The last time i drove the car though it sat right at the top for maybe a mile and did not go back to mid when i stopped and restarted car, i still did not think the engine was overly hot considering the gauge was hard pegged at the top. Thanks for any guidance it is much appreciated from this newbie!