Is there a creamy looking gunk on the oil filler cap? If so its the headgasket, if not its the oil cooler which is a common fault on the 1.7dti, I should know as ive had to change mine already at 130k
Why Is Oil Entering The Expansion Water Bottle On My Astra 1.7 Dti 2002?
The conventional cause for this is that there is a leak in the head gasket, a bad thing. It is also possible that coolant is mixed in with the motor oil, another bad thing.
The best thing you can do right now is to have both the coolant and the motor oil changed and then see about using a sealant product in with the coolant. It may work but should do no harm.
The best thing you can do right now is to have both the coolant and the motor oil changed and then see about using a sealant product in with the coolant. It may work but should do no harm.