stefan063

Like when the problems occurs or when everything is normal and do and when owners expect to get this problem?

Jonathan H

As in estimated # of miles that can be driven from right now (diagnosis of scored cylinder) until engine is disabled as a result of scored cylinder. What items would be most likely to fail and/or disable the engine in said scenario?

Just brainstorming more options when faced with a $12,000 potential repair on an ~$18,000 car.

OP are you willing to attach the estimate itself or a breakdown with parts/numbers?

​​​​​Knowledge is power!

deilenberger

Knowledge may be power - but in this case - it's all guesswork. It depends on how badly scored the cylinder is. Can't tell that without scoping the bore, and even then - it's subjective. I'd say the time is probably 1 minute to 5,000 miles. Heavily weighted toward the 1 minute.

It's not going to get better by itself. Your choices are - get rid of it now by basically selling it for parts value, or fix it and suck it up - and then maybe get rid of it. Neither are good options - but they're the only ones I see.

Jd_gts

All of the recent cylinder scoring threads have me paranoid... How exactly do you use the boroscope/inspection camera to check the cylinder walls? What's the best means of entry?

Thanks in advance!

pvanosta

To answer some of the recent questions:
1. the indy tried sourcing a used block but none were available in the region or at a competitive price, so we went with option 2 (rebore/resleeve etc)
2. I will attach any ppwk I get related to the repairs
3. I asked about the driveability. During the scoping they found significant fouling of the spark plug etc, which got cleaned. Now the engine runs smooth (even the CEL spontaneously cleared). They said to drive as little as possible and always only drive gently. I currently only use the car for unavoidable, short local trips, never engage the turbos and don't exceed 45 Mph.

oldskewel

I'm no expert on this, but I did it as my own PPI on my 2004 S last year. (thread on here about the whole process)

Easiest way is through the spark plug holes. That's what I did and I did not see anything to make me probe deeper. But ...

From reading other threads on here, with photos, etc., the scoring problem affects the sides of the pistons as well (obvious, I guess). And the scoring problem starts at the bottom of the cylinder. So it could be that you look in from the top (through the spark plug hole) and the cylinder wall that you can see (rotating the crank as needed to inspect as low as you can on all the cylinders you want to inspect carefully) looks good. But there could still be hidden damage behind and below the piston.

So it is possible to do a borescope inspection from below. I don't know exactly how it is done or how difficult it is (oil drain plug holes would be the obvious first things to try; oil pan removal would certainly get you the access you need). But it is possible, and could reveal problems that are undetectable from above.

I think usually during a PPI would be the time you'd really care about ruling out the scoring completely. Once you own the car, it's not as if detecting it early on would let you do anything about it. So I think these bottom-side borescope inspections are pretty rarely done. Also, if you do a complete and careful bottom-side inspection with a clean bill of health, it still does not guarantee you won't have problems later. But it depends on the cost of the car. The value of these cars has sunk so low, at least partially due to this problem, so sometimes it's most cost effective to just roll the dice.

oldskewel

Great info. Thanks.

Has your indy done this before? How common a repair is it over there? After searching through this site, it sure seems that over here at least, the block repair option is possible, but only by a select few.

That price point, $12k, does bring it into a much more feasible range, if it were available out here in the US.

Something I would be interested in is what the actual block repair cost is. So if I ever needed to do this, and did the full disassembly, etc. myself, and then shipped the scored block away, what is the cost to repair it? Not that I'd ship anything to Europe of course, but just curious.

For me and possibly others going forward, if we like working on cars and count our labor as free, the major repair cost would come down to mainly that item.

Good luck with the repair. Hopefully you're factoring the risk involved into your decision.

Petza914

If I had a scoring problem on either my Cayenne or my 997, there is only 1 place I would go to have the block work done and that's LN Engineering (www.lnengineering.com) where they would repair and resleeve using Nickasil cylinder liners. This stuff is so hard that it's virtually indestructible, and after paying to have this fixed once, I'm sure I don't want to roll the dice that it could happen again.

If not doing the rest of the rebuild myself, I believe Carl at 928 Motorsports does some Cayenne engine work as well.

NelaK

I think in North America, you could do the block repair and parts for around $10k.

928MS and LN engineering both list the block repair services + new pistons and other needed components for around $5k.

What we're missing is information (AlldataDiy seems to have most of the assembly procedure but it's hard to trust it until someone has taken the risk to verify it) and a cheaper source for all the other bits and bobs you'll need from Porsche.

oldskewel

Good info, thanks. For me, at $10k with me doing all the work, it still does not make sense considering the alternative of just buying another one and hoping for the best (after thoroughly inspecting).

I know there are a few cars out there that even warrant the full $25k pro rebuild, like Petza914's of course.

But even if I thought my car was worth $10k (probably not even half that is a better estimate), it would not be worth the risk to invest $10k on the repair and hope nothing goes wrong. Not for me, at least.

deilenberger

Just a reminder: https://rennlist.com/forums/cayenne-...ific-poll.html - bore scoring poll - unashamedly unscientific - but I'm working on a better one if we can get Internet Brands to kick in some money for a poll subscription.

pvanosta

Quick update: got my car back today:
- new engine block (with new pistons, crankshaft, timing chain, ...) with 2 years Porsche warranty
cost, including labor: 12,000 Euro

Now the car basically has a new engine which will outlast the life of the vehicle, especially with the low miles I put on it.

Dan87951

Sorry to hear! I hope you're able to get it fixed.

If I were in your situation, I would look into nikasil options, I found it very reasonable when rebuilding my 928 engine. Good luck and keep us posted.

J'sWorld

So you got a short block through Porsche?

pvanosta

Yes. The indy first tried to have the original block re-sleeved but Porsche couldn't deliver the other parts necessary (pistons, camshaft, ...). They could however deliver en entire block with pistons, camshaft, timing chain, etc. So that is the route we took. It has the added benefit of 2 years' Porschwe warranty and the cost difference was minimal.