The Cayman's DME (Digital Motor Electronics) records the number of ignition cycles that occur when the engine speed passes 7,300 RPMs. It also records the 'hour' of operation in which the incident took place. These records can be retrieved by using a PIWIS or Durametric Diagnostic Cable. The information can be used by a Porsche dealer to deny a warranty claim when abuse is the cause, or by a potential buyer to identify abuse of a used Cayman.
There are six ranges of over-revving that are logged by the DME:
Don't be alarmed if you see 1,000 or more cycles in a range. That sounds like a lot, but keep in mind that a Cayman engine sees 3 ignition cycles per revolution. You can determine how much time was spent in the range by using the following formula: Time at Over Rev = Ignition Cycles / (RPM/20) . So, 1,000 cycles would be less than 3 seconds, or more likely, three 1 second bumps into the rev limiter.
It is possible to use aftermarket software to erase over-rev records, so this test should not be used as a definitive or exclusive identifier of abuse. If buying a used Cayman, a pre purchase inspection conducted by an experienced Porsche repair shop or dealership is a very good idea.
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