Hello all, I have a 2001 Corsa (new shape) with the 1.7 Turbo Diesel engine fitted which appears to be getting oil in the cooling system. The car runs well and doesn't use any oil or water but develops a black line of oily sludge above the water line in the expansion tank after a few days running. I've checked the oil cooler for leakage (pressure tested) and refitted with new seals but it's not the cause, has anyone any suggestions or come across this problem before?
