Quote:
Originally Posted by Ptriggiani
I recently purchased a 2000 S with 102K miles , 1 owner full service records, recent clutch, rms, IMS bearing and many other new parts. I had a independent Porsche shop go through the car with only 1 comment regarding camshaft deviation, 5.4 and 8.2 readings. After placing and reading several postings on the subject I had decided to have the chain ramps and guides replaced before putting it on the road this spring. This past week I had a lengthy discussion with a recently retired Porsche technician . He was a graduate of the academy, with 35 years experience at the only Porsche dealership here in Maine. For many of those years he was the head technician at the dealership. His response to my situation was to drive the car with enthusiasm as it was designed to be driven. He said that the computer controls were very sensitive to any situation that was out of specification and I would have ample warning if anything had potential for trouble. He commented that he did not regularly check camshaft deviation unless he had a drivability issue or check engine light to give him reason to do so. He went on to say that without previous readings I would have no idea if this was recent change or could have been this way for many years. I had already called the independent Porsche shop that had serviced the car for many years and they had never checked for camshaft deviation either.
I am now wondering if the whole issue of camshaft deviation has been blown out of proportion and in fact many unsuspecting owners are driving around with camshaft deviation numbers beyond limits and no problems.
My car idles smoothly with no noise on cold start , and no check engine light.
Any thoughts , comments , etc regarding the above?
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The system limits are +/- 6 degrees; measurements should only be taken the engine is fully warmed up, like after a drive, otherwise the results would be meaningless.
Cam deviation values are useful for two purposes: First, if they are swinging back and forth wildly at idle, something in the can drive (read IMS) is coming loose and caution is necessary. Second, if the values are steady but outside the limits, it is sign of chain tensioner wear pads wearing out and needing to be serviced. In either case, the car will run fine and not code, but both require steps to correct before problems set in.