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YOUR RESEARCH2003 c4s ?slight pitting bottom of cylinder 5?
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Replace brake
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Performed · outcome unconfirmed · Original poster
The actual vehicle in question still needs the following services to be "solid" minus the above: Trans full service, water pump thermostat (original, proactive maintenance), IMS needs to be checked, so replaced, Brake check, pads I think are around 50%, headlight resto (cheap, no biggie), and my guess is while you're in there for all that stuff there will be other items.
Leading evidence: 'Replace brake' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Clean engine 80k+ miles examples are actually out there' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed · Original poster
will do, the CEL was a bad coil so they replaced all coils (and plugs?).
Clean engine 80k+ miles examples are actually out there
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Suggestion · Original poster
I guess the question I want to know is how many clean engine 80k+ miles examples are actually out there.
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Suggestion · Original poster
Oil filter was clean of debris but had a recent change so doesn�t mean much.
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Suggestion
I know because I had to change the crank and con rod bearings so I had to take the engine completely apart.
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Performed · outcome unconfirmed · Original poster
The actual vehicle in question still needs the following services to be "solid" minus the above: Trans full service, water pump thermostat (original, proactive maintenance), IMS needs to be checked, so replaced, Brake check, pads I think are around 50%, headlight resto (cheap, no biggie), and my guess is while you're in there for all that stuff there will be other items.
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Suggestion · Original poster
Had an extensive conversation with the PPI mechanic and then my mechanic before the test drive about the potential pitfalls and cost to get the vehicle running, this clearly has changed.
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As the title suggests, just had a PPI completed on an 03 C4S. Results came back ok minus one issue. Shop did a bore scope and said there was very very small pitting in the bottom of cylinder five. Suggested maybe the car had sat for a while. Car is reasonably priced and fits my needs. What should I make of this? Oil filter was clean of debris but had a recent change so doesn�t mean much. Wondering how common this is for engines that last a very long time still or if I should walk. Car has 87k miles, SoCal car all it�s life.
Will be trying to get a picture of the pitting, not the vehicle. Calling the shop back today after I wrap up some meetings. It was stated that it was pitting, did not look like scoring but I figured anything strange related to cylinder walls was worth posting/thinking twice about.
In terms of when in doubt walking away, very familiar, took me a long time to find the right 89 3.2
Attached are photos of the pitting at the bottom of cylinder #5. How common is this on higher mileage cars? Doesn't look anywhere near as bad as what I've seen in Jake's videos but still curious on it.
Are the red arrows the pitting? And the silvery band pointed to by white arrows a light reflection? Also I see vertical lines across the entire picture.
According to Barry Hart of Hartech these engines were cast with a cylinder coating "Lokasil" that has hard silicon particles in it, and at some point they start coming off. Earlier engines had iron coated pistons and silicon bits harmlessly washed away by oil and filtered, our engines have plastic coated pistons and those allow hard particles to embed in piston and destroy cylinder. Fortunately many engines run 200k miles or more without this happening, and it can be delayed by using thicker oil, lower temp thermostat, and not lugging engine. Remedy is mill out Lokasil cylinder liners and have Nikasil cylinders installed, that's about $5k with pistons, then there is overhaul of the rest of the engine and installation $10-20k total depending how much labor you do.
That's not what I would call "pitting", that's what I would call small "chunks" coming loose, you can see where they skidded down leaving streaks.
I hate to see that, I would not buy that. That car just took a huge hit in depreciation in my opinion.
Isn't that a little like saying why are you looking for a 996? Or any car with Lokasil cylinders?
I think the odds are that if you look at any 996/997 that is 15-20 years old and has tens of thousand of mile on it you are going to find conditions like this.
Ok everyone, drove the coast 2 hours each way today (tough life, was in the 3.2) and test drove the car. Below are my thoughts:
1. Interior is achingly beautiful. Nice leather, smelled rich, very little wear for a car this age.
2. Outside was a bit tired but also gorgeous. Headlights could definitely use a refresh but did not look like 18 years of sun damage. Body was in decent condition, clear stress cracks in the front from bumper tapping and some swirling/light very small scratching on all body panels, consistent with what you would expect from a car this age. Rear bumper below the reflector strip, there are some noticeable scratches in a vertical pattern that make out a triangle, rather large but not deep enough to be bothersome to me (I love patina, subscribe to the preserve not restore ideology).
3. Tip was not nearly as bad as I remember and the transmission was actually great to drive (the PDK is marvelous but I don't actually like how fast it is, loses some mechanical slowness that makes driving fun vs. dangerous on public roads). It downshifted way better than the 993 tip I remember driving in the early 00s.
4. Car threw a CEL 10 minutes into the drive after getting her up to temp and doing a light/medium pull onto the highway. Drove right back to the dealership at slow speeds and informed them. They are going to put it into the service bay on Monday and call me back. Had an extensive conversation with the PPI mechanic and then my mechanic before the test drive about the potential pitfalls and cost to get the vehicle running, this clearly has changed.
Rating 1 out of 10 but I would play again!
Cheers for the long weekend and hope you all have a good one!
Myles
For those that have read about our opinion on the causes of bore scoring (report available from
[email removed]
) they will realise that this is the sign of the start of cylinder bore particle release that a lot of similar cars of this age and mileage will be experiencing. In many ways your photo proves the myth that there are other causes - you simply have to admit there was material there originally and it is not there now so must have gone somewhere. The only space it can go to is that between the piston and the bore of which the piston is soft aluminium with a relatively soft plastic coating and the bore is aluminium with hard silicon particles embedded in it.
You have to ask yourself first - what is the material that is now missing from the bores - answer a mixture of alloy and hard pieces of silicon grit.
Secondly - what happened to them when they became lose - answer they were trapped between the piston face and bore until they washed away - or some might now be stuck on the piston face.
Thirdly - why no deep scoring yet - answer these are early stages and so far probably not stuck to the piston but just like a pot hole in the road the hole edges are where more particles will be released until a large enough particle sticks to the piston and rubs up and down forcing more particles out from the edges and scoring the bore.
Probably many examples look like this by now. this car probably has good piston coatings that are still largely in tact - if the piston coating had flaked off (pictures in our report) then the first released particle would probably have stuck to the piston and you would not see the holes but immediate scoring.
You would however probably be able to drive that car for up to 20 or 30K until it got so bad it needed fixing and if the price reflects the condition and it is probably going to be a keeper (and you could save for a decent rebuild in the meantime) if it is such a great example otherwise and only has the start of a problem they will probably all suffer - it could still be worth considering!
Good luck in your search.
Baz
thanks Baz, the price does not fully reflect the condition. This would turn into a 50k+ Porsche after two years of ownership so most likely will walk. I guess the question I want to know is how many clean engine 80k+ miles examples are actually out there. This has pitting but not real scoring yet. Is that and edge case or like 80% of 996s at this point?
Myles
Why I feel comfortable having booked a proactive build for later this year. Car has 78k miles on it and will be a long term or forever car (would only sell if I could somehow swing a 991.2 GT3 someday)that I hope to enjoy racking up miles on with no worries.
serious question;
once you spend the money on the proactive build, financially speaking, it will take 'forever' to amortorize your build. Or at least many years. Is that what makes it your forever car?😉
that said, I do agree you will have an awesome motor. It's the rest of the car that will hold back it's allure, considering your interest in the 991.2.
The intent wasn�t to hijack OPs thread so I�ll say this then move along: this October, I�ll have a killer 4.0L C4S with better/smoother power for less $ than what a 60k mile 997.2 would cost me. I find that pretty �alluring�. If I could buy a 991.2 GT3 today, I would. But I can�t, so I won�t. Maybe one day.
I did say financially speaking, in which i was trying to tie in to affordability of 991.2 GT3. So not a major factor, but one which will have impacted finances to purchase 991. That's all.
Thread was not hijacked bash
I think my situation/use case here is slightly different that would make the idea of doing a rebuild in a few to a few more years not really ideal.
1. This is going to be a daily driver, it will be parked outside a lot, it will get beat up, it will be however well maintained.
2. I'm already considering a "sacrifice" on the spec of the vehicle as it is a tip. I have a manual 3.2 and I just don't want to do the stick 9-5 in traffic in SoCal.
3. This car will see a much lower ratio of spirited to traffic driving than the weekend toy.
4. Why buy a Porsche to sit in traffic? Why buy a Porsche tip when you can easily drive stick all day in traffic? Well you're still wrapped in a Porsche and I just won't have it any other way at this point. 996s (minus a rebuild) are actually fairly economical. As for manual, its a concession to traffic but more importantly my significant other. She has not been driving long and is not able to drive a stick (yet).
So all of the sudden you have a vehicle worth somewhere between 20 and 35 normally with no engine issues that you put a 20k rebuild into and can never get rid of because it's a tip. The reason I would still even consider is a. probably won't ever sell a Porsche I buy (lesson 1, hold hold hold) and b. If the current motor lasts another 100k miles/10 years then a rebuild is much more reasonable.
I've heard multiple things about the pitting shown above. Two mechanics have stated that it is most likely due to the vehicle sitting for some amount of time, there was potentially a tiny bit of rust that seized the piston to the cylinder wall and on startup it took a chunk out OR it came from the factory with tiny pitting OR it's the beginning of bore scoring OR it's the beginning of bore scoring and I'll get good long use out of it still OR it's asking price + 4-5k to get it road ready + 20k in engine rebuild about 2 years.
The actual vehicle in question still needs the following services to be "solid" minus the above: Trans full service, water pump thermostat (original, proactive maintenance), IMS needs to be checked, so replaced, Brake check, pads I think are around 50%, headlight resto (cheap, no biggie), and my guess is while you're in there for all that stuff there will be other items.
I'm pretty religious about doing vehicle maintenance on time and it'll only be regularly driven in warm climates, but a lot of traffic.
Looks like I've started to ramble... The search continues, if any of you have a lead on a C4S with non black/grey/blue interior in good working order let me know?
So, did this shop perform the bore scope through the sump, as I describe in my part 4 of the "Focus on Bore Scoring" video series?
If not, they accessed through the plug holes, and it is physically impossible to see the "bottom" of the cylinders from that access point. What would appear to be the "bottom" of the cylinder when viewed through the plug hole, is actually mid- bore...
If that's the case, they say about 60% of the whole picture.. More lies underneath, literally
believe it was through the sump. To be honest I�m a little disappointed in the quality of the PPI in general. Write up was vague and not super informative, had to call a few times to get the photo, and things I would have expected addressed on the first convo were not. My local mechanic really spoiled me on his thoroughness.
that being said I have confidence in the shop that did the PPI, maybe just not the tech. Learning experiences for sure.
I believe it was through the sump but could be wrong.
just out of curiosity, how often does bore scoring start/progress with a single groove in the cylinder wall? I was under the impression that a large surface area typically scores with many grooves?
the other thing I thought was interesting was the idea that a car which has sat has rust issues inside the cylinder that seized the piston to the wall? I assume that isn�t a start it up and drive consistently and it goes away situation?
Every bore scoring situation starts with a single groove in the cylinder wall..
I would be willing to bet they did not pull the sump to do this. Unless they've seen my videos, they won't even know it can be done this way.
Mine has over 200K mile and the bores are still smooth as a glass. I know because I had to change the crank and con rod bearings so I had to take the engine completely apart. I've worked on many other kinds of engines over the years and even when the cylinders have a ridge from wear, the bores are still smooth.
The right C4S is out there. Mine was not perfect, and I paid $2500 too much, especially given what I know now about what needed to be replaced and updated, but, it was my first and won't be last go with a 911 and I'll be a driver for life. I spent a LOT of money with worn out parts in 2019, but had almost zero in 2018 (bot in Dec. 2017) and looking forward to hopefully none in 2020. Car has never left me stranded (I thankfully was at home when the battery expired and needed a new one) nor not started, etc. in now 26 mo's. of ownership. I had the whole front end and rear bumper resprayed this year too, so it looks great for a car it's age. Tbh I've thought about listing mine, if you're interested in talking about it at all, shoot me a PM. It's an '03, black on black, 94,3xx miles, Tip, Sport Techno wheels, it's my DD (only ~15 mi. per day). About halfway thru it's latest service, new-ish tyres, maintenance records since I've had it. Just throwing it out there!
will do, the CEL was a bad coil so they replaced all coils (and plugs?). I offered 19 and told them to call me back if interested. The response tells me not unless it sits a month or two.
ill reach out as I near my Augusta deadline and am still interested.
cheers,
Myles
No I don't. Each person must be guided by their own comfort level and make their own decision. The OP shared info about a car he is looking at and seeking advice on a possible defect. It had nothing to do with
our
personal financial decisions or how we make those. I was suggesting that, in my opinion, the OP should budget money for the possible future expense of an engine rebuild. I do not see your point.
I don't understand the comment. At 19k I'm comfortable with the risk on this vehicle. I have simultaneously reached out to the fellow rennlister who was thinking of selling. What have I missed here?
This is rather simple. A good used replacement engine is let's say around $10K plus a couple more K in labour if you can't do the work yourself. If you buy a Porsche rebuilt short block and have the heads swapped over, you will be around $10K too unless you can do the work yourself then, it will be around $1500 less. Keep in mind, you still have to pay for the core charge until Porsche checks out your old engine and gives the money back. So, if you can get this car for that much less PLUS a bit more to cover the potential headache THEN maybe it is worth buying it. From what you wrote so far, I would guess you are not comfortable doing any of this work yourself so there....
Risk is a funny thing, based on luck, probability, and information we have.
If I said that bore scoring affects 5% of M96 engines, the next question would be, what is the makeup of that 5% - what information can I gather to see if I�m in that 5%? A borescope image would probably be #1. So with this new information, this engine is probably 50-75% guaranteed to be in the 5%.
I was once on an airplane in the sky that got struck by lightening. When I tell people the story, they almost cannot believe it because it seems so unlikely. But with new information, it turns out that on average, a commercial airplane is struck by lightening about once per year, on average. So it happens to the plane 100% of the time.
It�s risky buying a 911 when we don�t have the information, but after getting good information, the risk is almost all but removed since we theoretically know the condition of the components.
All manufacturer engines '99 to '04 should run 200k miles before major work, including rebuilt/overhauled/remanufactured ones.
What percentage 996 engines make it to 200k miles including Flat Six Innovations and Hartech? That critical information I haven't seen anyone try to obtain.
I was on a tour of the Boeing facility in Seattle,, where they re-paint their planes, the top of the older planes were covered with .5 to 1.5 inch pock marks, from lightning. From what they said I was seeing about 7 years worth.. It was a lot of marks.... more than 7.. more like 50 to 100..
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