New member here. I've got a 98 Outback (2.5l) with 90,000 miles on it. The other day it overheated out of the blue, right after about 10 miles of highway driving. Temp shot up and I ended up with some coolant in the engine compartment. My mechanic took a look for about a day and couldn't find a problem. I did a little internet browsing and found out about the infamous "blown head gasket" on the phase 1 engine. My mechanic says no, there are no external signs of a blown gasket. Here's the way I see it:
1) mysterious overheating with no apparent external cause
2) bubbles in the coolant reservoir after driving
3) exhaust smell in the coolant reservoir
The mechanic sent me home with the car and said to call if it happens again, but I don't want to kill the engine "waiting".
Any thoughts?