What you are referring to is the problem with bent connecting rods. Pieces of carbon sometimes collect on the inlet to the intake manifold. Then break off and end up getting smashed between the piston and cylinder head. Therefore bending the connecting rod very slightly. Symptoms of this are loud pinging while the engine is running and/or excessive smoke. I have seen many of these engiens run with this problem for 200K plus miles. This problem will not show up on a compression test. The other problem I have seen is the oil pump drives breaking. Although isolated I have had two customers with this problem. It ultimately cost them an engine.
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