Hi, I have a 1999 Subaru Outback with ~81000 miles. On a recent trip the engine temperature started to fluctuate between overheat (top of the gage) and normal every few minutes. I found the oil level down 2 quarts which I added and the coolant overflow tank almost empty; I added water. I then drove car about 20 miles before getting it towed to a Subaru dealer. They found oil in the coolant and feel that either the head gasket is gone or in addition the block needs replacement.
They might be right, but I have some questions:
- If there is leakage between the cooling system and the oil why is there no water in the oil. I don't know the relative pressures.
- Why the oscillation in temp. This it seems to me might be caused by a bad thermostat.
I need a second opinion.
Thanks for help in advance.