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Old 10-06-2012, 01:22 PM   #12
The Radium King
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dunno if they need to (or if it is even possible to) retime the engine. what they can do is check/repair the usual suspects when it comes to excessive cam deviation. the first indicators are parts that porsche has improved over the evolution of the m96 engine. the first of these are the chain tensioners fpr which there is a new porsche part #. there are three of them at $100 each, they can be serviced without opening the engine, and a worn one can cause the chains to not have the requisite tension and rattle around.

the other parts improved by porsche are the variocam tensioner pads. they are plastic, and if failing will leave chunks or hard greeny-black plastic in your oil filter. these are the pads that control tension on the chains that tie the two cams together and vary the deviation. the new porsche part uses a harder plastic. you have to remove your cam covers to get to these, but the whole engine doesn't have to come apart. the process is detailed here:

Pelican Technical Article: Boxster Camshaft Upgrade / Chain Tensioner Replacement - 986 / 987

there are other chain tensioner paddles that can fail (and ln engineering offer an improved part for this) that require complete disassembly of the engine.

otherwise, the senors that send the deviation information to the computer can go out of spec, or not be in spec from the factory. of course, it is because of the info being provided by these sensors that you are concerned in the first place. aside from replacing them, what is suggested is to monitor your deviation over time and use. if it says steady at 9, it may be that it is a bad sensor. if it continues to worsen, this suggests that the info it is sending is good.

finally is the ims. if it is bad you have already lost the race. signs of a failing ims are deviation values all over the map (due to the death wobble of the failing bearing) and your symptoms do not indicate this. so replace it if you have the trans off to do the clutch, but otherwise i would look at the other culprits above first.
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