carsandcapp

reposting here. Here is the original thread: https://rennlist.com/forums/cayenne-...l#post16757880

"Apologies if this is a repeat but I couldn't find a post on this topic.
If you own a Cayenne Diesel, this is critical heads up for you.
When Porsche began selling the diesel units after the emissions scandal they added an extended warranty of 8 years/80K miles on the emissions and fuel delivery systems. There is also a mandated update to the PCM that reflects problems with the fuel filter (plugged) warning the owner to seek service. Here is the backstory:

Our daughters 2013 Cayenne Diesel w 37,000 miles ground to a stop enroute to her destination. She was pressing the accelerator and the vehicle was slowing down and when she pulled over the engine quit, and the dashboard warning lights all lit up. The was no other indication there was a problem, ie: strange noises, clunk, smoking, etc. Cutting to the chase the vehicle was towed to Rector Porsche in Burlingame, CA. The dealer discovered the fuel pump had grenaded (blew up, in their words) and sent shrapnel throughout the fuel delivery system. This is an engine-out repair process and complete disassembly/replacement of the fuel delivery system including the pump, injectors, lines and fuel tank flush. We learned the fuel system (and of course emissions related components) are covered by Porsche extended warranty. At any rate, this is a seriously expensive repair currently covered by Porsche. It would behoove anyone who owns one of these great Cayenne's to have their dealer validate that the PCM was updated to trigger the fuel filter warning, and to have the fuel filter changed regardless.

Dealer advised the fuel pump pressure is ~1300psi in the Cayenne diesel. The fuel filter is known to clog, and the rub is, the non-updated PCM SW does not contain the code to drive a cel when the filter needs changed. So the fuel pump builds even higher pressure due to a clogged fuel filter until ultimately the fuel pump nukes. This update is supposed to be performed by the dealer before selling the diesel Cayenne - ours was not updated (I'm not revealing the dealer where we purchased the Cayenne - it was not Rector). If not done, this catastrophic failure can result. Anyone with the diesel Cayenne should check w a P-Car dealer to ensure this PCM update is done. A passive indicator that the fuel delivery system is malfunctioning is fuel mileage. The diesel should achieve under normal driving conditions ~35mpg. Our daughters was averaging 31mpg. According to the dealer, the reduced fuel economy was sign that the system was failing. Don't get me wrong, these are fantastic vehicles and if I could find one I like I'd seriously consider trading my beloved Cayenne GTS. Hope this helps someone down the line..."


FYI, not sure I agree with the 35 mpg - under "normal" driving conditions. That seems pretty generous. And if you are worried about a grenading fuel filter in your CD, then change it out yourself. I did mine in May and it was an easier job than changing the cabin air filter. LOL.

KBell

Simple solution.
Change the fuel filter on the diesel.
Porsche recommends every 20,000 miles.
Do it every 10,000 miles if worried.
It is easy and very cheap if DIY.

reneeweiss

Where is the fuel pump located on a cayenne diesel 2013?

heeltoejunkie

The HPFP is in the “valley” of the engine. It’s a big job as the original post mentions. There is also a low pressure fuel pump, it’s below the rear seats.

reneeweiss

Thank you for the info. I assume you don't have to pull the engine to replace it, is that correct?