trublu97

2012 Porsche Cayenne TT, 114,000 miles.
Has anyone had a failed lifter? I got a check engine light, followed by the engine running rough, and was able to get home.
The mechanic indicated the lifter has failed.
No ticking sound. No warning, car was fine.
I going to talk further with the mechanic to make sure the diagnostics are correct.

lml999

Did you get a chance to pull codes? A bad coil pack could show similar symptoms, although with the V8, a single coil pack wouldn't make it run particularly roughly.

Lost a coil pack on my B5 A4 and I thought it had coughed up a lung. One dead cylinder out of four makes it run pretty rough...

trublu97

I have it at an indy shop and I will go talk to them in person. There was no ticking sound, so, I was shocked when they said it was a failed lifter.
I called the porsche dealer to see how many lifters they sold in the past year and it was zero, so not a common failure.

Quadcammer

I call bs on the lifter diagnosis. Suspect number 1 is always the coil pack. Even one failure tends to cause the car to be a bit rough and can cause all sorts of weird dash lights.

I'd try swapping coils from one cylinder to another and see if the code follows.

cathalferris

Are cam followers called "lifters" in the US, even though that's not actually a correct term? My understanding of lifters is in pushrod engines, not in overhead cam engines like our V8s..

trublu97

Yes, same thing.
It positions the valve based on cam movements.

trublu97

Talked to the Mechanic, and it is a bad lifter. The code reads out low lifter pressure. They checked the coil pack.
Sucks.
if the clearances are bad between the head and lifter, the engine is history.

996AE

Cost to repair more than car is worth?

Lifters generally do not toast a motor

Replace them and move along if all else good on car

Quadcammer

Hard to believe but ok. A used head would fix you right up if the clearances are bad.

DemonBG

What codes are you getting? I have never heard of a bad lifter on these engines... For what is at stake, get a second opinion or buy a scanner and pull codes yourself. You could also have a problem with the VVT solenoids which manifest as rough running / poor idle and those are a little more common.

trublu97

We will be getting access to the lifters over the weekend and we will see what we have. I am not sure how they work exactly, but talking to the mechanic the lifter will expand as you rev the car and open the valve more. As you accelerate, the lifter is not doing this function while the fuel system is injecting more fuel based on demand and new valve lift. With the valve not open as much as it should be, this causes the misfire. Too much fuel, not enough intake air.

It does seem to be rare. Lucky me.

trublu97

It is 12K for a low mileage swap engine.
Replacing he lifters will be 4000 for the lifters, plus labor.
If the head is bad, then it would make more sense to buy a replacement motor and salvage the current one.

trublu97

Ok, mechanics gained access to the lifter, the clearance btw the head of the lifter is OOS, I don't know the spec, I figure it is .003" and they measured .060.
I am not exactly sure how this works, but with that clearance the oil is blowing by and the lifter can not position the valve correctly.
And they found metal in the oil pan for good measure.
So, replacing the engine, found a long block with 56K.
Great, uh?

GTCharlie

Damn, this sux. LS Swap!

trublu97

Ok, update. I guess VW makes a direct swap lifter that is .050" larger than the porsche lifter and will drop right in and bring the tolerances back in spec.
no damage to the head, I guess the original manufacturing machined the bore large (error) and over time the wear on the lifter caused it fail.
We'll see if this works.