Hey guys, hope somebody can help me cos its starting to get on my wick now. I have an 02 Focus 1.8tdci. Last week the temp gauge started playing silly buggers and every time you let off the throttle the heaters started to blow colder air out, So i messed about with coolant system, dropped all the water out was horrible rusty brown, so started pulling each pipe and flushing them out, have done the radiator and the heater matrix aswell, today I changed the water pump and flushed the rad through and the matrix again, the thermostat was tested and worked correctly. Put it all back together spent over an hour trying to get it up to temp, the temp gauge reads normal, the top rad hose gets quite hot, the bottom hose was cold, the heaters are just the same, cold till you drive it soon as you let off the gas back to luke warm/cold. Please help as it is driving me round the bend