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Re: Subaru 3.0 low/no compression all cyls due to carbon buildup
Posted to Technical Discussion Forum on 1/15/2018

My thought is low rpm, short trip use and poor quality fuel. Carbon builds up on piston and eventually flakes off and gets between the valve face and seat. This causes compression loss. This may be a sign of excess oil use as well. You can bet the rings are sl... Login to read more.