I have a 56 plate suzuki swift 1.5, about two weeks ago the engine temerature gauge showed that the engine was over heating, so i took the car car to my local garage and they said they couldnt tell me what the problem was. while driving the car home the gauge started to rise rappidly so i turned the interier heating and vents to full and the engine heating gauge dropped to normal. I've sinced noticed the radiator fan kicks in after about eight miles, if i keep the interior heating and vents on full the engine doesnt overheat. If I turn the heating down the engine does overheat. Any ideas? Many thanks, Darren.