stan4life

Hello,

997 C2S 2006 manual 100k km. Just had a scope. Found bore scoring, zero symptoms. No IMS issues. What are my options ?

Thank you !

anewman

Drive it until there is a reason not to.

Sporty

How is the oil consumption?

stan4life

I drive couple thousand KM a year. Do an oil change before storing. Nothing to report.

Optionman1

That doesn't look bad, though I'm no expert. Not even sure that qualifies as bore scoring vs normal streaking that has been discussed in other RL posts.

plpete84

I'd monitor oil consumption, if there is any, and keep an eye out for any other symptoms. You can increase the oil change interval to 3k miles and starting a UOA is not a bad idea. Worst thing you can do is not drive the car IMHO.

gutenfreibier

What a bummer to find out! As stated above, it certainly doesn't look terrible as far as some of the other photos I have seen. There are some oils with moly additive you can use that supposedly slow this down. If you are only driving a couple thousand Km per year, you may have 10 or more years before needing a rebuild.

What caused you to look for the scoring? Was this scoped from the top (spark plug holes) or the bottom (sump)?

stan4life

Scope from the top. PPI.

I spoke to a few specialist today, they say all 3,8 engines after 100k km will have some sort of wear and tear in the cylinders. It is a none issue and a rebuild is not recommended. One said we can change the sleeves for 750 CDN a sleeve + the needed hours.

scottrx7tt1

Any engine starts to wear as soon as it is started up. You cannot expect zero wear on any engine regardless of mileage. All I hear is bore score, bore score, bore score. Everyone has been scared by this occurrence to where they just cannot enjoy the Porsche ownership experience. What other cars do you do you run a scope through to inspect the cylinders? I cannot say that I have ever done it with one single car.. if you did, you may find exactly the same wear as this or similar. Lots of people drive cars for hundreds of thousands of miles and get a lot reliable life out of their engines. I would not even be concerned until I started getting a misfire due to low compression or high oil consumption. I guess that’s just me. Don’t sweat it. Get out and drive your car

gutenfreibier

VERY well said! I have rebuilt numerous motorcycle, sxs, and car engines, and typically find some sort of "bore scoring" in most of the engines I have ever torn down. Nothing lasts forever. The air cooled camp seems to rave on and on about how robust the old engines are, yet they need rebuilds that rival or exceed the cost of a water-cooled rebuild too!

yvesvidal

You already did 100 thousand kilometers with it..... Why not continue? They all have some kind of score boring but that does not prevent them from running and performing very well.
Drive it until it consumes so much oil that you have to rebuild the engine. It may be years before that happens....

Yves

frybear

I have never scoped my 2005 C2S and I don't plan on it, because it doesn't matter. I have no symptoms, my tail pipes are all the same in terms of any soot etc. Car runs strong. But I am certain I probably have some scoring. I sent my oil off to Blackstone last year after I did an oil change (bought the car in September of 2021). Oil analysis came back with high metals all over the place. I switched over to Driven DT40 oil, and got the LN spin on adapter to use with the K&N gold filter. Per Blackstone's recommendation, ran the car for another 2000 miles and sent the oil off again for analysis - metals were greatly greatly improved. This is just my experience, YMMV. I am burning some oil though. Porsche says 1 liter/quart every 600 miles is normal - sounds like BS to me but whatever. I was maybe burning a 1/4 of a quart every 500 miles or so, which is why I think I might have scoring. Just drive the car correctly, no shifting above 3500 rpms until the car is completely warmed up and when you start the car, no idle - just get in and go.

rileyracing1

I tend to agree --- I would call that mild scoring at best ... Most of of cars will have a little of this in one cylinder or another .... Use good quality oil and some Mos2 and don't worry about it ... It can remain like that for years with no symptoms.

sandwedge

On the positive side, you don't hear IMS, IMS, IMS much anymore. With some patience I'd like to think the bore score hysteria will wear off just the same. As you say, how many here have had the cylinders scoped on any other car prior to purchase? I'm with you at exactly zero and never had an engine failure or even an engine issue on a number of sports cars of all kinds of brands. This includes three 997's btw. Current one is just shy of 70K miles and I think I'm getting upwards of 3,000 miles per quart.

Oil consumption is so low that I'm not keeping close tabs. No need to since I only drive it between 2,500 and 3,000 miles a year. Added no oil between the last oil changes and it was only down by one bar at the last annual change. Maybe they under filled slightly at the last change since one bar doesn't equal one quart as far as I know.

8KaboveMSL

OP, I also discovered my car had bore scoring in Dec of last year. It had 48k miles on it at the time, showed no consistent noticeable symptoms and was consuming about 1/4 qt of oil every 1k miles. The oil consumption was within "spec" and I didn't have any audible signs (piston slap). I asked my indy to do a bore scope from the top (in addition to a few other things) as I was getting ready to go on a cross country drive from CO to DC. Well, I discovered bore scoring (pics attached for reference below).

I am going to try to answer your question honestly, with the caveat that there is a lot we collectively do not know about bore scoring and how it plays out in the M96/97 engines. I think you have input from folks that have not had to deal w/ bore scoring yet above and all of those are valid responses. I am not writing to rebut any of that. Reasonable people will disagree on this topic because precisely because there is so much we don't know. In the end it becomes a very personal decision as to how to deal w/ either the prospect or evidence of bore scoring. I'll discuss what I did once I figured out I had bore scoring and also give you my perspective on what things I weighed. I do take the BS issue seriously and hopefully that doesn't put me in the hysterical camp.

Here is what I did. . .
Prior to discovering my cylinder bores were scored:

• Used DT 40 Oil
• OCI - 5k miles or 6 most, whichever comes first
• UOA at every oil change
• Installed LNE magnetic drain plug
• Installed LNE Low Temp Thermostat (LTT)
• Installed LNE Spin on filter adapter and used their recommend filters
• Kept revs under 3k RPM until Oil temp was close to 200 F

What I have done since discovering the issue:

• Reduced oil change interval to ~ 2.5k miles
• Started using Liqui Moly 2040(1 liter)/2041(5 liter) Synthoil Premium SAE 5W-40 Motor Oil which apparently has a superior detergent package to improve removal of any metal debris

All of these steps seem reasonable and are not by any way prohibitively expensive, so it all seemed fairly rational to me.

It's pretty clear that once the scoring process starts in the bores, it can't be reversed. The best one can hope for is to slow it down. If you drive the car, it's going to progress. The big question that none of us really know the answer to is: how long can one drive an m96/m97 engine w/ scored cylinders before the condition leads to a serious failure or a more expensive rebuild?

There are a few of us that are at that point in the process and we are trying to determine exactly that. Should we go for a rebuild now? Should we wait? Again the right depends on each one's circumstances. Do I daily my car or only drive it 2k mi/yr? Would I like to get more power/performance out of my engine? There are many other factors to consider, we are not all in the same situation. For me when I looked at the pros and cons this is what I saw:

Pros of doing a rebuild now:

• Ensure no unnecessary damage is done to the engine
• Parts for a rebuild while becoming more difficult to obtain are still largely available
• Cost of rebuild is likely to go up w/ parts shortages/inflation
• get an engine I won't have to worry about in the future if I do the rebuild right and address all the known failure points

Cons of doing a rebuild now:

• Could I have driven the car for another 20k - 30k miles before having to rebuild? Perhaps more?
• out of pocket expense (figuring somewhere between $20k and $30k) is a lot to stomach at once
• not a lot go trustworthy options for a rebuild if you're not going to (or capable of) doing it yourself
• the trustworthy guys have a decent backlog and are not cheap

There are probably points more but you get the idea. Anyone can look at this list and judge what can I live with and how much risk am I willing to swallow? The answer is not likely going to be the same for everyone.

In my case, I want to keep my car (I really do love it!). I am in line w/ one of the rebuilders awaiting an opportunity to get a slot. I have identified a local shop who can do all the work (trained at FSI) to remove and reinstall the engine after it is rebuilt. I have the cash set aside. I am driving the car and willl continue to do so until either my number comes up or I get piston knock. At that point it'll go into the garage until the engine can get rebuilt. Good luck! Whatever you decide to do, I hope you have a good outcome!


Cylinder 1

Cylinder 2

Cylinder 3

Cylinder 3.1

Cylinder 4

Cylinder 5

Cylinder 6