Check the thermostat housing it's on the bottom right hand side of the engine block as you look from the front. It should have 2 or 3 plugs/connectors going to it (depending on air-con) [lightbox=../../e107_files/public/1179932031_2253_FT176162_p2064335__thermo_switches.jpg][/lightbox] If it is as pic above then yes very common leak, replace the lot (housing, seals), parts are cheap enough