Buying a used Porsche can be a difficult and even stressful task due to the potential for expensive repairs. Anyone contemplating a used Porsche purchase should consider that at a minimum, a few thousand dollars will be needed to bring things into top condition. Many believe that problems like a worn out clutch, or even engine and suspension issues are the worst and will set you back a lot of money–and they can. However, the worst case scenario is a twisted or diamond shaped chassis (body) caused by an accident. Often you cannot visually tell just by glancing at the exterior of the car. In this situation, the chassis will never be the same no matter how much time or expense is invested.
The only way to lessen this risk is to send the prospective purchase for a PPI (Pre-Purchase Inspection) to a highly experienced Porsche repair facility. The chassis inspection should be top on the list, followed by the drive train, engine, gearbox, brake system, and finally, the interior’s condition. With the newer cars, i.e. the 964 and later, you then add the myriad of electronics and in the case of the 993, the SAI (Secondary Air Injection) system’s issues, stemming from worn out valve guides. All of these systems can be evaluated during a pre-purchase inspection. In the modern Porsches, the various control units can be interrogated including the POSIP (Passenger Occupancy Side Impact Protection) system “event data” to determine if there have been any accidents that have caused the airbags to deploy and the DME (Digital Motor Electronics) system to see if there have been any engine over-revs.
A thorough PPI can take up to four to six hours or more and provide the buyer with a lot of information and details; however, there are limitations as to what the PPI can tell you. Since major components are not being removed and disassembled, an experienced technician cannot tell if an internal component is developing a problem that could lead to a failure.
An often overlooked part of a PPI is to ask the owner if they can produce all the service records going back to when the car was new. This will give you tremendous insight into how this and/or previous owners have treated the car. Surprisingly, some owners treat these expensive cars like an appliance, stretching out the service intervals or not performing any preventive maintenance at all. Sometimes when this is encountered, it may be best to pass on a specific car even though the price may be attractive. In the long run, any pre-existing condition will become yours, so be persnickety in your decision.
Enjoy your Porsche,
Tony Callas & Tom Prine