The head gasket has a high failure rate due to cooling system problems. Subaru is aware of the problem and has extended the warranty to 8 years/100k miles on many vehicles.
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Subaru Impreza Outback Cooling System Problems Cause Head Gasket Failure
Subaru Impreza Outback Problem
7 Reports
Model Years Affected: 1998, 1999, 2000, 2001, 2002, 2003
Engine Affected: 2.5L 4 Cylinder
Verified
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Visitor, 2002 Subaru Impreza Outback, 2.5L 4 Cylinder, 75,000 mi
Began smelling the sweet smell of coolant burning as temps have dropped. Traced back to LH head, rear side. Dripping about 1 drop/min after shutting car down (until everything cools and the head-to-crankcase clearances join back up).
This followed after a recent coolant servicing. Application of Subaru Coolant Conditioner as instructed by the WRP-99 seems to have abated the leak for the time being.
Will be replacing head gaskets as soon as funds allow, as 8 yrs/100k miles was aptly chosen and we are now beyond that 8 yr limit!Flag ThisLike0