Of course, it could always be a lifter, but today it pays to assume the worst and hope for the best. If not you spend thousands to replace lifters that were never the problem, then you still have a problem that costs thousands more to repair.
Cylinder failures are often associated with cold weather operation, due to improper running clearances set by the factory, coupled with forged pistons. This faille has landed more engines at our facility as of late than any IMS Bearing related failure, and thats probably because people don't know how to diagnose it. Only 1 out of 6 of these engines that come our way comes here first before someone else throws a set of lifters at it, only for the problem not to be repaired.
Conventional leak down and compression tests and even bore scope these will NOT detect this issue, because the failure initially begins well below the point of BDC and the skirt is where the wear starts, so often times it takes a few thousand miles of operating with a tcl before the engine starts to burn oil. When that happens it will then progress to misfires rather quickly. Again, these are classic lifter symptoms, which will send most technicians into a tailspin.
The temperatures over this past winter took this issue that we normally only see from Canada and the upper mid-west and Northeast, and spread it across the majority of North America. I am currently working on an in-depth article about this for a magazine, because it needs to be revealed to shops and enthusiasts that have never heard of it.
These photos and associated text and captions explain it well. This engine failed at 27K miles after being used in the winter in Ohio, beginning in 2009 when this engine was installed as a factory crate Porsche replacement.
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