A PPI that includes a check with an enhanced scan tool or specialized scan tool (durametric/PIWIS etc) to check live camshaft deviation can tell you if the IMS is good or bad.
A PPI will also tell you the overall mechanical shape of the car, which is as important as the IMS!
You can also call all the shop where the car have been and ask them if they did perform an upgrade on the particular car you're looking at!
A friend in France has traced his Boxster all the way back to jacksonville Brumos Prosche and ask them directly about it
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