Diesel engine failure: advice
 

It happens to be a 2013 diesel Cayenne, but it happens to all brands of diesels, apparently. It has 188,000 miles. The engine lost significant power so I took it to a Porsche dealer. They said the high pressure fuel pump failed, releasing metal shavings throughout the fuel system. It would cost $30K to repair, so the car is worthless now. Is there any known simpler fix? Anyone familiar with this?

I would talk to a couple independent shops, the dealer will want to change everything to new parts, needed or not. Are they also installing a new engine for $30k?

It happens to all modern Tdi diesels with a HP fuel pumps, or at least it can. It happened to my VW but luckily it was still within the diesel gate warranty so it did not cost me anything. Now my car is throwing codes like a gang member in LA County lockup and I’m hoping that a tree falls on it, hopefully not with me inside.

If you are going to sell it as-is, send me a PM and maybe I’ll be dumb enough to take it on as a project. I’d have to find a crashed one with lower mileage that has not eaten itself yet. Good luck.

Common issue with modern diesels like already mentioned. One of my friends had his new Ram do the same thing and they had no replacement engines - said it was going to be at least 6 months for a warranty replacement so he ended up having to trade it in broken and buy another truck :-(

I swear this is caused by modern fuels. I use a diesel additive with almost every tank in my TDI. I also refuse to use a vw approved 5w30 in mine. I use Driven's DP40 instead.

Revisiting this...

The car is sitting in my driveway waiting for a mechanic, any mechanic, willing to work on it. No one wants to take it on. Back to the idea for a simple fix that I can take on. Can't I just replace the high pressure fuel pump and flush the fuel lines to get the metal shavings out? What else can be done? I see no reason to replace everything from the tank to the injectors. The car runs great until a sensor sends it into limp mode after maybe 30 minutes of driving.

Not a definitive answer but…why not? Nothing to lose at this point and may very well succeed.

Yes, modern fuels are crap, diesel and gasoline.

Father in law runs the additive to the diesel fuel and is sort of OCD on maintaining his stuff.

His last Chevy had 400,000 miles of overloaded with a trailer that is probably too heavy, ran great when he gave it to his son, who promptly wrecked it.

Is a motor swap not an option?

A good shop will flush the lines and the tank. Replace/rebuild the injectors. When injectors fail, they burn a hole in the piston(how many psi are the common rail injectors? 30,000 psi?). New fuel pumps.

No one wants to touch that headache tbh. Especially if frugality is in the discussion. Don’t clean the system enough and you’ll grenade another fuel system.

Find a wrecked truck.

There are a mess of Cayenne's being parted out online. I've always wondered why.

The cp3 in the Cummins 6.7 (stopped in the 2018 year model) are the standard for reliability in the common rail world. So reliability that kits exist to modify current CR engines for the cp3. Other failures such as fuel injector jetting a hole in the piston is the common failure for the fuel system.

Also there’s a kit that puts a filter on your return so if your vw hpfp poofs, it keeps the shrapnel upstream.

Why do these systems exist? Ask the nazis in California and the carb.

A friend has a VW Touareg with the diesel. I think it uses the same HP pump.
The pump is a known and common failure point with the results you have. The roller gets cock-eyed and things come apart. That pump might be considered a "wear" item. Maybe some lube added to the fuel will help as a preventative measure.

Writeup here....
INCR-EA11003-61863
PDF (static.nhtsa.gov)

1:30 ratio? That is a s#it load.

I know that diesels in general will run fine on ATF but I never thought of it as having much lubricity(?) Cleans everything in sight, that's for sure. There is a junkyard near our cabin in rural WI. where the owner has an older Chevy rollback/flatbed tow truck with ~500k miles on it and the guy claims that all he's ever run in it is used ATF drained from the hundreds of cars on his property. :)

Might want to brush up on your math. One quart to 30 gallons is not 1:30 ratio. :cool:

No, you had it right. But I used to add something a lot more oily, like a quart of outboard motor oil.

More so my reading skills :D

Early ones have the unicorn diesel.

1:30 equates to the 1 x to 30 y = 31xy.

I’m not going to do the math.


AtF in a common rail too?!