I began to note hard starting on my B15 2005 QG18DE with 60k miles and in about 1 week misfire at idle. Did a compression test with the following results: 158psi - 90psi - 90psi - 152psi. Also noticed water consumption and grim at the radiator fill neck. With these symptoms it was obvious the head gasket had blown so I replaced it. This is how I found the head gasket when the head was removed
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It was blown between cylinder 2 and 3. The engine has never overheated and Ive had it for over a year so I just replaced the head gasket. Once I put everything together again and started the engine the engine sounded good. After 3 hours driving, same symptoms appeared and the compression test gave the same results, same compression leak, same cylinders. I am guessing my cylinder head is warped? How can it warp if it has never overheated? Will a blocked cat create enough backpressure and cause this?
It was blown between cylinder 2 and 3. The engine has never overheated and Ive had it for over a year so I just replaced the head gasket. Once I put everything together again and started the engine the engine sounded good. After 3 hours driving, same symptoms appeared and the compression test gave the same results, same compression leak, same cylinders. I am guessing my cylinder head is warped? How can it warp if it has never overheated? Will a blocked cat create enough backpressure and cause this?
