99three

I may be paranoid but over the cold winter months I've noticed a higher than normal sound coming from the top of the motor. A knocking sound if you will. I have 124Km on the clock. Power is normal as is acceleration although I get the very rare oil smoke at start up. Oil consumption is a bit higher than normal but I've learned to chalk it up to Porsche high tolerances. Is this all pointing to another cylinder scoring problem. If so I'm extremely pissed....any recourse from Porsche????

I'm waiting for the warmer weather to perform a borescope, compression/leakdown test and change the coils.

Vivid7

pull your plugs and see if any are fouled.

brett968

Does it sound like this?


That's my car two months back just after I swapped in a clean used 116k mile engine. It sounds worse now but it still runs fine. I believe it is either cylinder 1 or 2 (as I understand it, this is unusual in that normally the problem starts on bank 2). Oil consumption has increased considerably. It's just a matter of time. Obviously, cylinder scoring is the culprit in my case. I'll be doing the engine replacement all over again soon.

With cylinder scoring, I wouldn't expect the plugs to foul until the problem has progressed to the point where the damage is extensive. You'll hear the tick long before this (assuming you're listening for it).

99three

That's how it sounds just not as loud. I think I caught it in its infancy. Is there any oil additive while I try to source another motor?

brett968

I'd save the cost of the oil additive and put it towards the new engine. My strategy while I try to source another engine is to restrict the miles (around town driving only) and rent a car when I need to travel any distance. I feel for you, this problem really sucks.

99three

I'm with you there. Additives are a minimal expense and since I'm driving it I'd like it to sound like a Porsche, not uncle Ludwig's 81 diesel Jetta. I'm extremely disappointed in Porsche and its shoddy engineering or lack of. This is not something I would expect from a racing pedigrees marque. I've owned a few cars and only one other marque has let me down - and did not cost as much as this pepper did! What a joke.

brett968

Yeah and it would be one thing if the problem could be rectified for anything remotely cost effective or low risk. Short blocks are not available from Porsche anymore. Rebuilds are expensive--it's hard to justify putting a $17k engine in a $6k car. Used engines are cheap but a total crapshoot--I'm essentially back in the same position I was 3 months ago with my wallet much lighter. I was fully aware of the cylinder scoring issue and did everything I knew to do to reduce my chance of getting a bad engine. I still pulled the short straw. (Funny thing is, my original engine went 270k miles before a chipped or bent valve took out cylinder 6.) I will not put another used engine into my car unless I can hear the engine running in person and I would recommend to others to do the same.

deilenberger

"Ceretec" has been touted to help. I think it's a myth, but it's cheap to try. As far as this sort of engineering failure - price doesn't = infallibility. Almost all cars have a wart or two hiding in a closet. Honda has some engines that one bank is prone to melting down rings and pistons. Ferrari has tons' of bugs - all tolerated because it's a FERRARI. What makes a difference is how the manufacturer handles the problem. German carmakers are loath to admit a failure of engineering, so any fixes they do are generally on the QT and not publicized.

Porsche is a bit better than the other German carmakers in they DO improve the design of replacement parts based on failures of the original parts. That's how they've gotten to iteration #23 for the ignition coils on V8 Cayennes. The thing that pisses people off is when they deny any assistance in fixing the problem. That's where they might improve - and I think they have after the class-action lawsuit for the 911 water-cooled IMS bearing, and the US NHTSA recall urged by people on this forum on the 2011 958 V8 engines. The 958 is prone to transfer-case failures - but in many cases, Porsche has been assisting owners well out of warranty, provided the car has less than 100,000 miles on it and a history of dealer servicing. One might hope this attitude would happen with the cylinder bore problem - but I suspect the 955/957 have simply gotten to a value position where it isn't worth fixing them in many cases.

BMW was particularly annoying to me - since they simply continued selling the same damn defective design part after a long record of failures of those parts. There have been one or two examples recently indicating that policy may have changed.

Petza914

99three, what year and model is your Cayenne? Have you read or posted in the Cayenne 955/957 bore scoring thread. There's a lot of good info in there.

In the video that was posted here, the light high speed ticking is the DFI injectors firing (957 generation), but the lower frequency knock is the sound of the scored bore and piston slap.

J'sWorld

Even on the 4.5, the quieter the engine is, the louder the injectors are. The injectors can be very clicky. But Brett's video is is knock/slap for sure.

Vivid7

yeah most car companies have their fair share of prone issues. From 1997-2004 I was into the Mitsubishi Eclipse/Eagle Talon turbo cars. Owned 3 of them. The 2nd gen Eclipse/Talons were prone to crank walk which ended up eating the engine. The crank has a ton of play in it. Many of us at that time and hundreds of others in the DSM community experienced it. The issue was with the block. To fix you had to source and rebuild a 1st gen block. Nothing like turning a corner and the clutch goes straight to the floor with out you touching it. Crank walk time....

rileyracing1

The lighter sounding tick is normal but the knock on that video does not sound good ..... You need to scope the cylinders ( just go buy a camera if you don't have one from Canadian tire for a $100 bucks. No miracle in a bottle will cure a knock. My Cayenne 2005 v8 burns no oil from oil change to oil chage. 148,000km on it.
What brand and weight of oil are you using ?? Does the knock go away when the engine warms up .
we both live in Toronto and it has been quite cold lately which does contribute to an initial knock on warm up but should go away upon warm up .

James1911

Can someone post a picture of what the plugs would look like with cylinder scoring please?

Vivid7

some will look like normal dry used plugs. others may may be completely covered in oil.

99three

Checked the oil today and it's down about 1 litre in 1000 Km. Getting a compression test and scoped - will report back.