The Porsche owner's guide to knowing your car.
Repair guides by model, known issues explained without dealer markup justifications, service interval breakdowns, and local repair referrals — focused entirely on Porsche. If you drive a Porsche in Simi Valley, this is built for you.
Everything Porsche. Nothing Else.
We cover the full Porsche lineup — from the 911 and Boxster to the Cayenne and Macan. Every section is built around the questions Porsche owners actually search for.
911, Boxster, Cayman, Cayenne, Macan & Panamera
Generation-by-generation breakdowns: what each model is known for, which years to avoid, what high-mileage ownership looks like on Simi Valley roads.
Browse Models →IMS Bearing, Bore Scoring, Coolant Pipe Failures
The recurring issues across every Porsche platform explained clearly — including what a real fix involves versus a temporary solution.
See Known Issues →What Every Porsche Needs — and When
Engine oil specs, PDK fluid intervals, spark plug schedules, coolant pipe inspection windows, and the items Porsche dealers don't volunteer.
View Service Info →Buying Guides, Warranty Rights, PPI Checklists
What to inspect on a used Porsche, how to evaluate a pre-purchase inspection report, and what ownership costs look like year over year.
Read Guides →Repair Write-Ups, Ownership Realities, Tech Explainers
Regular posts on Porsche-specific topics: which model years represent the best value, what a full service costs at independent vs. dealer rates.
Read Posts →Ready to Book? Find Porsche Service Near You
Simi Valley's dedicated European auto repair shop — factory-level diagnostics, OEM-spec parts, honest pricing. 15 years working on Porsche vehicles.
Schedule Service →Porsche Known Problems — Explained
Every Porsche platform has its patterns. These are the issues that come up across the 911, Boxster, Cayenne, and Macan — in forums, in pre-purchase inspections, and in shop conversations.
IMS Bearing Failure — 996 and 997 Porsche 911, Boxster, Cayman (1997–2008)
The Intermediate Shaft bearing in the M96 and M97 engine is the most discussed Porsche failure point of the modern era. The bearing runs in engine oil but has limited lubrication and can fail catastrophically, destroying the engine with little warning. Affects every M96/M97 engine: 996 911 (1997–2005), 997.1 911 (2005–2008), all Boxster and Cayman through 2008. The LN Engineering IMS Solution or bearing replacement is the standard preventive fix. How to assess whether a car you're considering has had the repair, what the procedure involves, and the cost comparison between the retrofit and catastrophic engine replacement. Read the guide →
Bore Scoring — Cayenne V8 and Some 997.1 911 Engines
Cylinder bore scoring occurs when the Nikasil cylinder wall coating is damaged by combustion products or inadequate lubrication at the bore surface. In Cayenne V8 engines and some 997.1 911 cases, the bore degrades and leads to oil consumption and eventually compression loss. It's progressive — caught early with a compression and leakdown test, it can sometimes be managed; found late, it requires an engine rebuild or replacement. How to detect bore scoring before purchasing a used Porsche, what symptoms look like in daily driving, and what the repair actually costs. Read the guide →
Coolant Pipe Failure — Cayenne V8 (2003–2010) and Panamera
The plastic coolant pipes in the valley of the Cayenne V8 engine become brittle with age and heat cycling, eventually cracking and causing coolant loss deep inside the engine bay. The repair requires significant disassembly — labor is 8–12 hours — and is invariably expensive. The pipes themselves are cheap. The replacement is widely recommended as a preemptive service on any Cayenne V8 past 80,000 miles or over 10 years old. How to identify early coolant loss on these engines, what the repair involves, and whether a preventive replacement is worth doing proactively. Read the guide →
PDK Transmission Service — 997.2, 991, Macan, Panamera
Porsche's PDK dual-clutch transmission is exceptional when serviced properly and problematic when it isn't. Porsche specifies a fluid change interval that most owners miss or ignore — and dealers don't always proactively recommend it. The PDK uses a separate hydraulic circuit for the clutch pack and a gear oil circuit for the gearbox, both requiring specific fluids on their own intervals. What the full PDK service involves, how often it should be done, and what delayed service looks like in terms of symptoms and repair costs. Read the guide →
Macan 2.0T and 3.0T Engine Oil Consumption — All Generations
The Macan shares its engine family with the Audi Q5 and is subject to the same direct-injection oil consumption tendencies. The 2.0T in particular can consume oil between service intervals — not enough to trigger a warning light, but enough that owners who don't check their dipstick can run low. What the consumption rate looks like in practice, when it crosses the line from "within spec" to "needs attention," and what the correct diagnostic path looks like when consumption becomes a concern. Read the guide →
Find Your Porsche
Every model page covers the full generational history: what changed between generations, which years to prefer, known weak points, and what a thorough pre-purchase inspection should cover.
Porsche 911
996 (1997–2005), 997.1 (2005–2008), 997.2 (2009–2012), 991 (2012–2019), 992 (2019+). IMS bearing concern on 996/997.1. 997.2 and later are significantly more reliable. Generation comparison, ownership costs, and what to inspect at every era.
911 Model Guide →Porsche Boxster
986 (1997–2004), 987 (2005–2012), 981 (2012–2016), 982/718 (2016+). 986 and 987.1 share M96/M97 IMS concern. 987.2 onward uses the direct-oil-fed bearing. A well-maintained 987.2 is one of the best value sports cars in the used market. Guide covers every generation.
Boxster Model Guide →Porsche Cayman
987c (2006–2012), 981c (2013–2016), 982c/718 (2016+). Shares 987 platform and IMS concern on early cars. The mid-engine layout gives the Cayman arguably better handling than the 911 at lower price points. What each generation means for service and reliability.
Cayman Model Guide →Porsche Cayenne
9PA (2003–2010), 958 (2011–2018), 9YA (2019+). 9PA V8 has coolant pipe and bore scoring concerns. 958 is the reliability sweet spot. 9YA is the most refined and reliable generation. SUV cost of ownership guide for all three.
Cayenne Model Guide →Porsche Macan
95B (2015–2023), 95B facelift (2019–2023), J1 EV (2024+). Shares VAG platform with Audi Q5. 2.0T and 3.0T V6 options. Oil consumption monitoring, PDK service, and transfer case fluid service are the primary maintenance items. EV generation guide included.
Macan Model Guide →Porsche Panamera
970 (2010–2016), 971 (2017+). 970 V8 shares the coolant pipe concern with Cayenne. 970 twin-turbo V8 is particularly complex. 971 is a substantial improvement in reliability and refinement. What executive sedan Porsche ownership costs versus the alternatives.
Panamera Model Guide →Porsche GT3, GT4 & Turbo
991.1 GT3 engine recall history. 991.2 GT3 and GT4 with naturally aspirated 4.0. 992 Turbo S ownership costs. What high-performance Porsche maintenance actually requires beyond the standard service schedule — and what modifications do to your warranty and resale value.
GT & Turbo Guide →Porsche Taycan
First gen (2020+). What EV Porsche ownership means for service: 800V charging architecture, 12V battery system maintenance, brake service intervals (regen extends pad life significantly), and software updates. What still requires conventional service and what doesn't.
Taycan Model Guide →What Your Porsche Actually Needs — and When
Porsche ownership costs more than most cars to maintain properly — but it costs far more to maintain improperly. The service items that Porsche dealers don't proactively recommend, the intervals that protect expensive components, and what your money is actually buying.
Engine Oil Service — Spec and Interval
Porsche specifies C30 or C40 rated synthetic oils depending on engine generation. 911, Boxster, and Cayman: 10,000-mile or annual intervals using approved specification oil. Never extend beyond manufacturer intervals on air-cooled or high-performance water-cooled engines. What the spec means and which oils meet it.
Oil Service Guide →PDK Fluid Service
Porsche recommends PDK fluid changes every 30,000–40,000 miles in practice, even if dealer service advisors sometimes suggest "lifetime fill." The clutch circuit and gearbox circuit require different fluids. What the full service involves, how to verify your shop is doing both circuits, and what degraded PDK fluid looks like in shifting behavior.
PDK Service Guide →IMS Bearing Retrofit — 996 and 997.1
If you own a 996 or pre-2009 997 and have not had the IMS bearing replaced or upgraded, this is the single highest-priority service on the car. The LN Engineering IMS Solution is the current standard. What the procedure involves, how long it takes, and why coupling it with a clutch replacement saves significant labor cost.
IMS Retrofit Guide →Coolant System Service — Cayenne and Panamera V8
Preventive coolant pipe replacement on the 9PA Cayenne and 970 Panamera V8 is recommended at 80,000 miles or 10 years. Cooling system flush and thermostat replacement should accompany the pipe work. What the full coolant system service involves and why the labor cost front-loads the value.
Coolant Service Guide →Brake Service — 911 and Cayenne PCCB
PCCB (Porsche Ceramic Composite Brake) rotors are a specialty service requiring specific knowledge and pads. Standard iron rotor service has its own intervals. Brake fluid service every 2 years is critical on high-performance Porsche models given elevated operating temperatures. What to expect at each service point.
Brake Service Guide →Spark Plugs & Ignition
Porsche's flat-six and V8 engines use iridium plugs with a 40,000–60,000 mile service interval depending on generation. Turbocharged models are on the shorter schedule. Worn plugs on a high-compression Porsche engine increase ignition coil stress and can cause misfires that store codes erroneously pointing to injectors.
Ignition Service Guide →From the Blog
Technical write-ups, ownership cost breakdowns, and Porsche-specific analysis — written for owners who want to understand what they're driving.
997.1 vs. 997.2: Why the 2009 Model Year Is the Most Important Dividing Line When Buying a Used 911
The 997.2 moved to a direct-oil-fed IMS bearing design, eliminating the single biggest reliability concern from the 996 and 997.1 era. What else changed between the generations, why the price premium is often worth it, and what to inspect when evaluating either car.
Read PostUsed Porsche Cayenne Buyer's Guide: 9PA vs. 958 — Which Generation Offers the Better Value Proposition
The 9PA is cheaper and has more known failure points. The 958 is more expensive and significantly more reliable. How to evaluate condition on both, what a pre-purchase inspection should specifically cover, and what realistic ownership cost looks like at each price point.
Read PostThe IMS Bearing: What the Failure Actually Looks Like, Why the Retrofit Works, and Who Should Do It
A clear explanation of the IMS bearing failure mechanism, what the LN Engineering retrofit involves versus a standard bearing replacement, and why choosing a shop that has done this procedure many times matters more than the part brand.
Read PostPorsche Owner FAQ
Should I do the IMS bearing retrofit on my 996 or 997.1 if it hasn't failed yet?
Yes, if the car doesn't have documentation showing the retrofit or updated bearing has already been done. IMS bearing failure destroys the engine without meaningful warning — a ticking noise in the final stages is the only pre-failure indication most owners get. The retrofit costs $1,500–$2,500 at an independent shop and is most efficiently done when the clutch is already out. If you're buying a used 996 or 997.1, this service history should be part of your evaluation criteria. The absence of documentation is not confirmation the repair was done.
What's the difference between a 997.1 and a 997.2 Porsche 911?
The 997.1 ran from 2005 to 2008 with the M97 engine — still using the M96-derived IMS design. The 997.2, introduced for the 2009 model year, redesigned the engine with a direct-oil-fed IMS bearing, DFI direct injection, and a new PDK transmission option. The 997.2 is meaningfully more reliable and more fuel-efficient. It also costs more on the used market — a premium that is, in most cases, justified by reduced catastrophic failure risk alone.
Is the Porsche Macan reliable enough to buy used?
The Macan is among the more reliable Porsches in the lineup — primarily because it shares its platform and drivetrains with the Audi Q5 and Q7, which have well-documented service profiles. The main concerns: PDK fluid service history, Haldex or PTM rear differential service, and oil consumption monitoring on the 2.0T. A pre-purchase inspection from a shop with PIWIS or VCDS capability should include a compression test, transmission scan, and fluid condition check. A well-maintained Macan with clean service history is a solid choice.
Can I take my Porsche to an independent shop without voiding the warranty?
Yes. The Magnuson-Moss Warranty Act prohibits Porsche from voiding your factory warranty because you serviced the car at an independent shop, provided the work was done correctly with parts and fluids meeting Porsche specifications. Keep documentation — receipts, fluid specification records — in case of a warranty dispute. CPO warranty terms vary slightly, so review your specific coverage agreement. The core factory warranty protection is federal law.
What does a Porsche pre-purchase inspection (PPI) actually cover?
A thorough PPI on a 911, Boxster, or Cayman should include: compression and leakdown test on all cylinders (IMS failure starts showing up here), bore scoring assessment, PDK or manual clutch inspection, full PIWIS or equivalent scan of all control modules, brake system inspection including PCCB condition if equipped, cooling system check, oil analysis, and a road test under load. On a Cayenne V8, add visual coolant pipe inspection and bore scoring check. A PPI costs $200–$400 and is the most important investment you can make before buying any used Porsche.
Ready to book your Porsche service in Simi Valley?
We've covered the research. When you're ready for the actual work — IMS retrofits, PDK service, diagnostics, or a pre-purchase inspection — we refer Simi Valley Porsche owners to the shop we trust.
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