New guy here. My 08 Impeza started throwing codes last week. First was P0028 (Intake Valve Control Solenoid Circuit Range/Performance Bank 2). OK, got a new battery, oil change, and changed the plugs. 4 days later another code - cylinder 1 misfire. I called Subaru and made an appointment for this Friday. Sunday it started with the high temp light and the heat wouldn't work. Brought down to Subaru and dropped it off (maybe a 7 mile drive). Got a call from the dealer that the head gasket was blown (which should be covered under the extended warranty). He said he had to do some other work, but it shouldn't be more than a couple of hundred $$ (the service manager is a friend so I don't think he'd sell me stuff I didn't need). My question is what would cause a head gasket to go? I service my car regularly and this is the first inkling of any issue (beside the transmission being replaced at 45k miles - again under warranty). Any idea what wouldn't be covered under the extended warranty that would need to be done?
