[Jake Raby]

Or its got a failing cylinder... If you drove the car over this past winter in Pennsylvania and started it up in those extreme temperatures, I'd ensure a thorough diagnosis is carried out. AS failing cylinder with the M96 sounds EXACTLY like a bad lifter. It will fool even the best, most seasoned Porsche technician.

We are seeing this occur all over North America and folks are wasting money to address lifters when thats not the problem. They won't realize thats not the problem till the lifter job is done and the noise is still there..

Diagnosing the failing cylinder is also not simple, and standard procedures for diagnosis won't work. The engine will still pass a leak down and compression test while in the early stages of cylinder failure, and it will even pass a bore scope test many times.

Approach with great care, I have a Pittsburgh car here right now that suffered this failure, was misdiagnosed and 8K (wasted) later it had to come here to be resolved.