I have just done a trip of about 200 miles, mainly motorway driving around 70mph, but some town driving. The car in question is an '03 reg astra sri 16v ac. Problem is it drank it's whole tank of oil. It's not in the coolant, it's not leaking onto the drive and I haven't noticed it smoking. Other symptoms, may be unrelated, are the aircon has died and the responsiveness in first gear is very very slow to pick up. It has been ongoing for just over a week now and it's fortuantly still under warranty from NetworkQ and going into the garage tmrw. Anyone have any thoughts as to what this could be?