Shops quote $12,000–$18,000 for this one, and the quote usually isn't the ripoff, the job really is that big. Here's what's actually failing, what the correct repair involves, and the honest part: this is not a job I do in a driveway.
The 997's 3.8 uses Lokasil/Nikasil-type coated aluminum bores instead of iron liners. Cylinders 5 and 6 sit at the bottom rear of the flat-six where they run hottest and get the least generous oiling, and over time the piston skirt starts wearing through the bore coating. Once the coating breaks down, aluminum runs on aluminum, and the bore scores, vertical scratches you can eventually hear as a distinctive cold ticking from the driver's side of the car.
A scored bore stops sealing. Compression on that bank drops, oil gets past the rings and burns as grey smoke on start-up, and combustion gases start pushing into the cooling system, which is why coolant level slowly falls with no visible leak. A compression and leak-down test pinpoints it fast, and a borescope through the plug hole confirms it visually, you can see the score marks.
Caught early, this does not need a new engine. The repair is to pull the engine, machine the damaged cylinder for an iron or Nikasil sleeve, and fit a new piston, restoring the bore better than factory. Left too long, the scoring spreads, the piston skirt collapses, and you're into a full rebuild or replacement engine, which is how dealers arrive at $12,000–$18,000 quotes.
If your Porsche is doing any of these, this is the likely cause:
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See how that range compares across Mississauga, Oakville, Milton, Brampton and Etobicoke in the GTA Repair Price Index, honest shop & dealer ranges for the jobs people actually get done.
Cylinder Bore Scoring Repair (Sleeve & Piston) is on my published list of jobs I turn down. It needs a hoist, a press or a machine shop, and I work out of driveways with hand tools. That list is public on my trust page. I'd rather lose the job than learn it on your engine, and you should be suspicious of anyone who says yes to this over the phone.
So here's what I can genuinely do for you, holding a $12,000–$18,000 quote. Both are real, both are flat-priced, and both are worth more than a bad yes.
Before you spend $12,000–$18,000, have someone independent confirm that's actually what's wrong. This is a diagnosis, not the repair, no hoist, no lift, nothing comes apart. I scan it, test it, look at it with you, and tell you straight whether their diagnosis holds up. If it does, I say so and you go pay them with confidence.
Book the second opinion →At $12,000–$18,000 on a car that might be worth not much more, plenty of people replace instead of repair, that's a completely reasonable call. If that's where you're heading, get the next car measured before you hand over money: 150 published points, at the seller's location, written report the same day.
Book a pre-purchase inspection →Tell me what you've been quoted and what the car is doing. $100–$250 flat, at your location, and you get a straight answer either way.
Rather just have the quote read? The free quote check tells you whether the number is in line, no visit needed.
Jobs on this car that ARE mine:
Not so you can do it yourself, so you can tell whether the shop quoting you understands the job:
That's the job. It's why this one belongs on a hoist instead of in a driveway, and it's why $12,000–$18,000 usually isn't a ripoff, it's a big repair honestly priced. What's worth checking is whether that's really what your car needs.
Get the diagnosis confirmed firstPlain version: Cylinder Bore Scoring Repair (Sleeve & Piston) needs equipment a driveway doesn't have, a hoist to get under it properly, a press or a machine shop for the parts that come out, and a controlled space for an engine or gearbox that's in pieces for days. I work out of driveways with hand tools. That's not false modesty, it's the published limit of what I take on, and it's listed on my trust page alongside the warranty.
What that means for you: this page is here to tell you what's failing and what it should cost, so you walk into a shop knowing the job instead of nodding at a number. And if you want that number checked before you pay it, that part I can do, $100–$250 flat, at your location.
Bore scoring only travels in one direction. Early on, it's one or two cylinders that can be sleeved while the rest of the engine is healthy. Keep driving on it and the score deepens, the piston skirt hammers itself apart, debris circulates through the engine, and combustion gas pressurizes the cooling system until it overheats. At that point a targeted sleeve repair becomes a complete engine, the difference between a repairable problem and a car-totalling one is usually a few thousand kilometres.
Diagnosis comes first, always. A cold-engine listen, a compression and leak-down test, and a borescope through the spark plug holes will either show the score marks or rule them out. Plenty of 997 ticks turn out to be lifters or exhaust leaks, we confirm before anyone talks about pulling an engine.
A properly machined iron or Nikasil sleeve with a new piston is, if anything, tougher than the original coated aluminum bore, it's the same approach the well-known Porsche engine rebuilders use. The repaired cylinder ends up more score-resistant than the factory one.
No. Cylinder Bore Scoring Repair (Sleeve & Piston) is on my published list of jobs I turn down, it needs a hoist, a press or a machine shop, and I work out of driveways with hand tools. I'd rather lose the job than learn it on your engine.
Two things, and both are real. A second-opinion diagnostic at your car, $100–$250 flat, at your location, so somebody independent confirms that's actually what's wrong before you commit to a $12,000–$18,000 repair. And if you're weighing replacing the car instead of fixing it, a pre-purchase inspection on the replacement, $149–$399 flat, at the seller's location.
Because the useful part isn't the wrench. It's knowing what's actually failing, what the correct repair involves, and that shops quote $12,000–$18,000 for it, so you walk in knowing the job instead of nodding at a number. If you want that number checked before you pay it, that part I can do.
Send it over for a free second opinion. I'll tell you straight what the job actually involves, and if their quote is fair, I'll tell you that too.
Get a Free Second OpinionOther makes:
I'm not the guy who does this repair. I'm the guy who tells you whether you actually need it, before you spend $12,000–$18,000. Second opinion at your car, $100–$250 flat, in Mississauga, Oakville, Milton, Brampton and Etobicoke.
Book a Second Opinion Inspect a Replacement CarYour options on this one