|
A "DME Report" when part of a PPI is done to look into how the car was driven and possibly abused. A thorough and proper PPI includes a DME report, especially on later model Porsches.
Porsche also uses the DME report for warranty claims to determine, among several issues, if the engine has been over-reved, or 'chipped', just to name a couple.
In older Boxsters (986 and 996) the DME only captured 2 ranges of over-revs. Over revs in range 1 were considered "OK". While over-revs in range 2 were "bad" and pointed to the owner missing a down shift. You can get range 1 over-revs from hitting the rev-limiter in strong acceleration and shifting at or near redline. Range 2's occur on a missed down shift (and spins) since the rev-limiter does not work 'on the way down'.
In the 987/997 series Porsches, the DME started capturing 6 ranges of over revs. Range 1 and range 2 are "OK" and normal. I would suggest range 3 is not good. Range 4 is a bit of a gray area. And range 5 and 6 starts to mean Porsche will deny a warranty claim for abuse.
In the DME Report, a time stamp (in total engine hours) is noted when the most recent event occurred. This gives very valuable info, as well.
Another way a DME Report is part of a proper PPI is to somewhat validate the car's mileage. You can calculate the average MPH, and make a judgment if it is consistent with the car's history and condition. Also give indication if the car was mainly city or highway driven.
Here are some DME over-rev ranges:
|