Hello all I know there are a few threads on this but may as well ask! My car temp was running very low, to the point it would go down to the bottom. So today I got a garage to replace the thermostat, bleed the system and top up the coolants etc. upon driving the car back the temp rose to above 2/3rds so I whacked the blowers on and drove it back tothe garage. They said it was bled for 45 mins, so they concluded it could be the head gasket (pressure test req) or maybe the heater matrix. I'm taking their word that they have fully bled the system so am wondering in the other things they mentioned could be a possibility? Any help would be great Cheers