Damn! Car in for #6 cyl scoring. Which way to go?
#136
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Lateralgrip (03-01-2022)
#137
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I think extremely cold ambient temps can hasten the problem, not necessarily because of temp swings themselves on any given day but the temp swing from when the engine was machined. I think it's safe to assume that the engine was not machined when it was resting at the likely most extremely cold ambient temp so, after tolerance stack-up, the engine could be really "tight" when cold. Add in a little cylinder oval-ity and/or hot spot and/or <<add any other single technical/operational shortcoming>> and you've got scoring. And once scoring is starting, I imagine it only gets worse.
Didn't LN Do videos about Bore scoring, and said "Its from the piston plating coming off"
Please correct me if Im wrong, but im 99% I seen the video in the last week. But I remember them showing the "bad cyl. , and the Bad Piston exterior finish gone or chipped off/away. Verse ones that were good.
And How many are failing under 10%?
No matter the reason, It really sucks. Sorry to hear. Why not drop the $7500.00 motor in and trade up or keep? The cars are hot right now.
Last edited by BNB911; 01-29-2022 at 04:54 PM.
#138
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I refuse to believe that a single cylinder with scoring cannot be fixed with either a coating or plating. I think there a lot of people selling engines and builds and are forcing this market as it makes them money.
Second, I think class action is imminent. A 135k car should last more than 100k miles. My car has been serviced more frequently than the Porsche schedule, and was inspected and scoped 2 years ago. My car started smoking last week, and popped a CEL, and now I have rod knock. This car was never tracked, driven constantly and properly serviced.
This. Is. A. Design. Flaw.
Porsche should fix every 997 with bore scoring.
Second, I think class action is imminent. A 135k car should last more than 100k miles. My car has been serviced more frequently than the Porsche schedule, and was inspected and scoped 2 years ago. My car started smoking last week, and popped a CEL, and now I have rod knock. This car was never tracked, driven constantly and properly serviced.
This. Is. A. Design. Flaw.
Porsche should fix every 997 with bore scoring.
Apparently you bought a Porsche thinking it was going to be as reliable as a Toyota Camry? That’s funny.
As for fixing just one cylinder, thats funny too.
#139
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I dont know about most of the other members here, but I wanted a 200k version of the 911. But my budget allowed for a very clean 2006 997. 52?K miles.
I purchased car knowing about the bore issues, and a rebuild was 25k ish. Who knows what a trans is or if they are even a problem. I drive it like I stole it, ***** to the wall.
Motor goes, giving LN a call. It is what it is, from below described life style of mine.
My middle class problem, is that I have enough money to get me nice expensive USED toys that cost more than I could ever afford new.
But I go into this knowing that I will pay for over time verse day one.
Please do not include me in a class action, I purchased used as is.
The Op, who bought new, noted problems, went out of warranty, now has the problem, Maybee from what I have read. I really hope it all works out!
Just remember you always catch more with Honey than vinegar. Truly wish you the best of luck.
I purchased car knowing about the bore issues, and a rebuild was 25k ish. Who knows what a trans is or if they are even a problem. I drive it like I stole it, ***** to the wall.
Motor goes, giving LN a call. It is what it is, from below described life style of mine.
My middle class problem, is that I have enough money to get me nice expensive USED toys that cost more than I could ever afford new.
But I go into this knowing that I will pay for over time verse day one.
Please do not include me in a class action, I purchased used as is.
The Op, who bought new, noted problems, went out of warranty, now has the problem, Maybee from what I have read. I really hope it all works out!
Just remember you always catch more with Honey than vinegar. Truly wish you the best of luck.
#140
#141
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Didn't LN Do videos about Bore scoring, and said "Its from the piston plating coming off"
Please correct me if Im wrong, but im 99% I seen the video in the last week. But I remember them showing the "bad cyl. , and the Bad Piston exterior finish gone or chipped off/away. Verse ones that were good.
And How many are failing under 10%?
No matter the reason, It really sucks. Sorry to hear. Why not drop the $7500.00 motor in and trade up or keep? The cars are hot right now.
Please correct me if Im wrong, but im 99% I seen the video in the last week. But I remember them showing the "bad cyl. , and the Bad Piston exterior finish gone or chipped off/away. Verse ones that were good.
And How many are failing under 10%?
No matter the reason, It really sucks. Sorry to hear. Why not drop the $7500.00 motor in and trade up or keep? The cars are hot right now.
In 2009 with the 997.2 Mahle switched back to a harder, plated coating that may scratch a bit it doesn't flake, along with a different monolithic block/cylinder construction (Alusil). It seems to have improved things considerably as borescoring is less frequent (anecdotally), but it isn't perfect unfortunately.
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BNB911 (01-29-2022)
#142
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Didn't LN Do videos about Bore scoring, and said "Its from the piston plating coming off"
Please correct me if Im wrong, but im 99% I seen the video in the last week. But I remember them showing the "bad cyl. , and the Bad Piston exterior finish gone or chipped off/away. Verse ones that were good.
And How many are failing under 10%?
No matter the reason, It really sucks. Sorry to hear. Why not drop the $7500.00 motor in and trade up or keep? The cars are hot right now.
Please correct me if Im wrong, but im 99% I seen the video in the last week. But I remember them showing the "bad cyl. , and the Bad Piston exterior finish gone or chipped off/away. Verse ones that were good.
And How many are failing under 10%?
No matter the reason, It really sucks. Sorry to hear. Why not drop the $7500.00 motor in and trade up or keep? The cars are hot right now.
#143
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I think thats the hardest part, everyone has a reason or cause for the scoring. Regardless of the issue does anyone have a real number on % of cars that fail based off a set miles, or motor. I heard 10%?
Overheating issues,
Pre 2005 was the IMS,
05-08 Bore score, Either way its a huge major problem for the 911/997.1.
09-12? EFI fuel injected no scoring issues yet?
Pick your poison.
years / models may not be exact, but The trend here is that every year or series run model has some problem. Just like Ford, Chevy, Dodge.
At the end of the day for what any of the toys or trucks cost they are all junk. But we still sign the line and turn the key!
Just remember "You can't take it with you."
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sburke91 (01-31-2022)
#144
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“Porsche: just assume the car we just sold you won’t make it to 100,000 miles, because, well, we are Porsche….”
Raise the W flag right now, CDK…. You win.
#145
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I know Baz Hart at Hartech has implicated the coating (it's actually not a plating, that's the problem), not sure if Charles at LNE agrees. Sometime around 2000 - 2001 Mahle switched to a soft polymer coating that is sprayed on as opposed to a hard coating that is attached via electroplating. That soft coating can start to flake and lift off, leaving aluminum to aluminum contact. In Baz's tech report he shows photos of pistons with flaked off coating that they were lucky enough to observe and catch before borescoring started and destroyed the evidence. There are other factors such as silicon particles breaking off the cylinder walls (made using Lokasil) and gouging the coating, not to mention other contributors like the cooling issue with cylinder 6 and not frequent enough oil changes.
In 2009 with the 997.2 Mahle switched back to a harder, plated coating that may scratch a bit it doesn't flake, along with a different monolithic block/cylinder construction (Alusil). It seems to have improved things considerably as borescoring is less frequent (anecdotally), but it isn't perfect unfortunately.
In 2009 with the 997.2 Mahle switched back to a harder, plated coating that may scratch a bit it doesn't flake, along with a different monolithic block/cylinder construction (Alusil). It seems to have improved things considerably as borescoring is less frequent (anecdotally), but it isn't perfect unfortunately.
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dubsiren (01-29-2022)
#146
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That will NEVER happen with ANY 997 as I understand it. If you own a 997, your cylinder walls are eating themselves as we speak. You can drive it, park it, oil it, tune it up, and it won’t make any difference.
The engine is a timebomb.
The logic I am hearing here is, “well, you bought a Porsche, of course it is a timebomb”. This is absolute bull****. Not ALL 911’s are destined for catastrophic engine detonation. Absolutely the opposite. We have all heard the stories of 70s era 911’s with 600k miles on them running just fine.
Look, I am a Porsche fanboy. I love them. I am looking for an old 911 as I type this. But this 997 situation is garbage. They skated through the IMS issue (somehow), but I think in the next 5 years, when we see waves of 997s grenading, it is going to be a problem for them.
#147
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I know Baz Hart at Hartech has implicated the coating (it's actually not a plating, that's the problem), not sure if Charles at LNE agrees. Sometime around 2000 - 2001 Mahle switched to a soft polymer coating that is sprayed on as opposed to a hard coating that is attached via electroplating. That soft coating can start to flake and lift off, leaving aluminum to aluminum contact. In Baz's tech report he shows photos of pistons with flaked off coating that they were lucky enough to observe and catch before borescoring started and destroyed the evidence. There are other factors such as silicon particles breaking off the cylinder walls (made using Lokasil) and gouging the coating, not to mention other contributors like the cooling issue with cylinder 6 and not frequent enough oil changes.
In 2009 with the 997.2 Mahle switched back to a harder, plated coating that may scratch a bit it doesn't flake, along with a different monolithic block/cylinder construction (Alusil). It seems to have improved things considerably as borescoring is less frequent (anecdotally), but it isn't perfect unfortunately.
In 2009 with the 997.2 Mahle switched back to a harder, plated coating that may scratch a bit it doesn't flake, along with a different monolithic block/cylinder construction (Alusil). It seems to have improved things considerably as borescoring is less frequent (anecdotally), but it isn't perfect unfortunately.
https://lnengineering.com/education/...s-navarro.html
In the Gen 2 cars, Porsche did make changes, but I still have seen both bore scoring and piston seizing which are two separate issues with similar end results. Baz had posted about this in the past where the bores are shrinking at the bottom near the main webs. This is caused by latent stresses in the castings and made worse by the very tight piston to cylinder clearances which we have documented at .0007" cold which is very tight for a forged piston.
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#148
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View Poll Results: Poll: Have you had bore scoring on your 997.1 or 997.2 engine?
Yes, 997.1 (05-08 MY)
![](https://rennlist.com/forums/images/polls/bar2-l.gif)
![](https://rennlist.com/forums/images/polls/bar2.gif)
![](https://rennlist.com/forums/images/polls/bar2-r.gif)
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107
13.84%
Yes, 997.2 (09-12 MY)
![](https://rennlist.com/forums/images/polls/bar3-l.gif)
![](https://rennlist.com/forums/images/polls/bar3.gif)
![](https://rennlist.com/forums/images/polls/bar3-r.gif)
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12
1.55%
No, 997.1 (05-08 MY)
![](https://rennlist.com/forums/images/polls/bar4-l.gif)
![](https://rennlist.com/forums/images/polls/bar4.gif)
![](https://rennlist.com/forums/images/polls/bar4-r.gif)
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422
54.59%
No, 997.2 (09-12 MY)
![](https://rennlist.com/forums/images/polls/bar5-l.gif)
![](https://rennlist.com/forums/images/polls/bar5.gif)
![](https://rennlist.com/forums/images/polls/bar5-r.gif)
![](https://rennlist.com/forums/clear.gif)
232
30.01%
Voters: 773. You have already voted on this poll
Yes, 997.1 (05-08 MY)
![](https://rennlist.com/forums/images/polls/bar2-l.gif)
![](https://rennlist.com/forums/images/polls/bar2.gif)
![](https://rennlist.com/forums/images/polls/bar2-r.gif)
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107
13.84%
Yes, 997.2 (09-12 MY)
![](https://rennlist.com/forums/images/polls/bar3-l.gif)
![](https://rennlist.com/forums/images/polls/bar3.gif)
![](https://rennlist.com/forums/images/polls/bar3-r.gif)
![](https://rennlist.com/forums/clear.gif)
12
1.55%
No, 997.1 (05-08 MY)
![](https://rennlist.com/forums/images/polls/bar4-l.gif)
![](https://rennlist.com/forums/images/polls/bar4.gif)
![](https://rennlist.com/forums/images/polls/bar4-r.gif)
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422
54.59%
No, 997.2 (09-12 MY)
![](https://rennlist.com/forums/images/polls/bar5-l.gif)
![](https://rennlist.com/forums/images/polls/bar5.gif)
![](https://rennlist.com/forums/images/polls/bar5-r.gif)
![](https://rennlist.com/forums/clear.gif)
232
30.01%
Voters: 773. You have already voted on this poll
#149
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If I break the 997.1 votes from the 997.2 votes:
997.1 Model
Yes Red = 107
NO Yellow = 422. Almost 25% failure rate.
997.2 Model
yes blue 12
no pink 232. Under 10% Failure?
Im tired, so feel free to check my math.
997.1 Model
Yes Red = 107
NO Yellow = 422. Almost 25% failure rate.
997.2 Model
yes blue 12
no pink 232. Under 10% Failure?
Im tired, so feel free to check my math.
Last edited by BNB911; 01-29-2022 at 07:48 PM.
#150
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I spend about a year in my free time researching this topic in depth and put out this paper several years ago. I go over everything that we know of to this point that can contribute to the problem. If you are at all interested, it's a good, albeit, very technical read.
https://lnengineering.com/education/...s-navarro.html
In the Gen 2 cars, Porsche did make changes, but I still have seen both bore scoring and piston seizing which are two separate issues with similar end results. Baz had posted about this in the past where the bores are shrinking at the bottom near the main webs. This is caused by latent stresses in the castings and made worse by the very tight piston to cylinder clearances which we have documented at .0007" cold which is very tight for a forged piston.
https://lnengineering.com/education/...s-navarro.html
In the Gen 2 cars, Porsche did make changes, but I still have seen both bore scoring and piston seizing which are two separate issues with similar end results. Baz had posted about this in the past where the bores are shrinking at the bottom near the main webs. This is caused by latent stresses in the castings and made worse by the very tight piston to cylinder clearances which we have documented at .0007" cold which is very tight for a forged piston.
Last edited by BNB911; 01-29-2022 at 08:14 PM.