#borescoring

Porsche 996 IMS Solution Installation and Preventative Maintenance: What You Need to Know

If you own a Porsche 996, you've likely heard about IMS bearing failures and other engine-related concerns that can turn into costly repairs if not addressed proactively. In a recent video hosted by Vu Nguyen of the Porsche Club of America, with commentary and technical guidance from Jake Raby (Flat 6 Innovations) and Charles Navarro (LN Engineering), a full drivetrain removal and Porsche 996 IMS Solution installation is documented on Vu’s personal 1999 Porsche 911.

This extensive walk-through isn’t just about replacing the intermediate shaft bearing—it’s about addressing a wide range of pattern failures and performing preventative maintenance to ensure another 100,000+ miles of trouble-free motoring.

Why Drop the Engine? Fixing What Isn't Broken (Yet)

While many IMS bearing replacement jobs can be performed with the engine in the car, Vu’s early 1999 996 underwent a full engine-out procedure. The reasoning? Access, visibility, and peace of mind.

“We’re fixing things that aren’t broken—yet,” explains Charles Navarro. “It’s major surgery, but the goal is to avoid future failures and enjoy the car with confidence.”

By removing the engine:

The IMS Solution can be installed cleanly and accurately.

Other wear-prone components can be inspected and replaced.

The job becomes easier, cleaner, and more thorough.

What Makes the IMS Solution Different?

The LN Engineering IMS Solution is a permanent, oil-fed bearing replacement for M96 engines. Unlike the original sealed bearing or retrofit kits that still require periodic replacement, the IMS Solution eliminates the service interval entirely by providing continuous engine oil lubrication, similar to how the factory designed the system in later engine revisions.

Jake Raby, who helped develop and test the IMS Solution, notes:

“The IMS Solution was created for long-term reliability. It’s not just a fix—it’s an engineering upgrade.”

Additional Maintenance Performed During the IMS Solution Installation

While the engine was out of Vu’s car, Jake and Charles tackled numerous known failure points and wear items typical of high-mileage 996s:

✅ Cam Chain Wear Pads

Using Durametric software, Vu confirmed cam deviation angles of up to -9°. That’s above the recommended threshold and signaled chain ramp wear, justifying replacement of the timing chain guides and chain ramps.

✅ Timing Chains

While replacing the ramps, the 4th and 5th timing chains were also replaced—an inexpensive yet smart decision to avoid rework later.

✅ Air-Oil Separator (AOS)

A known failure point, the Porsche AOS was replaced with a genuine factory part. Failures can lead to excessive crankcase vacuum, poor running, oil ingestion, or even catastrophic engine damage.

“A bad AOS doesn’t just smoke—it can suck oil into the intake under vacuum and cause a hydro-lock,” explains Jake.

✅ Oil Pressure Sensor

Intermittent idle drops and gauge fluctuations led to a preemptive replacement of this commonly failing part.

✅ Fuel Injectors

Given the age and ethanol-related issues, new injectors were installed. Over-fueling from worn injectors can worsen bore scoring and affect performance.

✅ Oil Filler Tube and PCV Conduits

Cracked or leaking filler tubes introduce unmetered air, richening the mixture and stressing the AOS. Replacing this often-overlooked part was a smart move.

✅ Accessory Belt Rollers and Tensioners

Original metal rollers were swapped for updated versions. Some rollers have been known to seize and cause crankcase damage.

✅ Motor Mounts

Vu replaced the rear motor mounts—often leaking by this age—with fresh fluid-filled units to restore engine stability.

AC Compressor and Header Removal Decisions

Vu and Charles opted to leave the A/C compressor in the car, avoiding opening the refrigerant system. This helped minimize invasiveness and the chance of leaks later. They also weighed the pros and cons of removing the exhaust headers—a job made easier with the engine out, but one that risks shearing off bolts.

Lessons in Organization and DIY Preparedness

A key takeaway from the video: organization is everything when doing a job of this scale.

Vu labeled and bagged every part using a Sharpie

Bolts were laid out in removal order

Videos and photos were taken as self-generated reference material

Jake recommends using cardboard templates to track bellhousing bolt locations to prevent mismatched reassembly (which can crack the engine case)

Diagnostic Tools: Durametric for Cam Timing Deviation

Before pulling the engine, Vu used a Durametric system to check camshaft deviation. This is a non-invasive way to verify the condition of the timing chains and guides. If deviations exceed -6°, it’s usually time for further inspection—and potentially engine-out service.

Other Proactive Replacements and Considerations

Starter motor: Consider replacing if slow to crank, but beware that newer units may be lower quality than original factory parts.

Ground strap: A corroded ground strap can lead to poor charging, hard starts, or strange electrical gremlins.

Crankshaft Position Sensor: Known to fail with heat. Vu’s symptoms matched exactly.

Coolant Hose Couplers and Engine Oil Coolers: If intermix has occurred, replace them to avoid failure from hose degradation.

Why This Approach Matters

This isn’t just about installing an IMS Solution—it’s a comprehensive engine rehabilitation. The goal isn’t just to fix a known issue, but to address all the age- and mileage-related vulnerabilities of a 25-year-old sports car engine.

Jake sums it up:

“You’re fixing what’s not broken yet. That’s how you get 5 to 10 years of reliable use out of a 996 without being stranded.”

Watch the Full Series

Lifter Tick or Bore Scoring? Why Misdiagnosis Could Cost You Thousands

In the world of Porsche M96 and M97 engines, few topics are as misunderstood—and misdiagnosed—as lifter tick. What sounds like a harmless ticking noise can actually be the early warning sign of a far more serious issue: cylinder bore scoring.

Jake Raby of Flat 6 Innovations has encountered this scenario countless times, and in a recent Rennvision technical video, he shares critical insights every Porsche owner, technician, and prospective buyer should hear.

The Problem: Lifter Tick That Isn’t

Each week, Flat 6 Innovations receives multiple inquiries from Porsche owners convinced they’re experiencing failed hydraulic lifters. Many have already spent thousands replacing lifters or camshafts—yet the ticking persists.

In most of these cases, the true cause of the noise is bore scoring, not a failed lifter. Unfortunately, by the time this is discovered, owners may already be out thousands of dollars with no resolution in sight.

A $14,000 Lesson in Misdiagnosis

One example Jake shares involves a deployed U.S. Navy sailor whose 2006 Cayman S exhibited ticking noises. A dealership replaced the lifters. The sound remained. Next, they replaced the camshafts. Still ticking. Total cost? Over $14,000—and the actual problem, bore scoring, wasn’t addressed.

Upon return, the vehicle was sold at a significant loss and the new buyer sent it directly to Flat 6 Innovations for a proper engine rebuild. This scenario, unfortunately, is not uncommon.

Why Bore Scoring Sounds Like a Bad Lifter

Bore scoring creates a rhythmic, metallic tick that mimics lifter noise. The tone, pulse, and location can fool even seasoned technicians unfamiliar with the M96/M97 platform’s specific failure modes.

In fact, Jake Raby admits that even he was once misled by this same acoustic illusion nearly two decades ago—and that experience is what drives his passion for educating others today.

🔗 Hear what bore scoring really sounds like in this sound comparison video from LN Engineering: 👉 Porsche Bore Scoring Sound

Lifter Failures Are Rare—and Behave Differently

While Porsche lifters can fail, they usually don’t produce audible ticking. Instead, they tend to cause:

Misfires, often felt before heard

Negative lash, where a lifter holds the valve open

Interrupted exhaust note, especially at idle

DTCs like P0300–P0306, indicating misfires

Jake emphasizes: "If you do have a lifter issue, it will usually cause a misfire before it causes noise." In contrast, bore scoring produces a tick without a corresponding misfire, making it easy to misinterpret.

Other Tick-Like Noises (That Aren’t Lifters Either)

Not every tick is bore scoring or lifters. Jake highlights three additional culprits:

Loose Spark Plug – Especially on M96/M97 engines, a loose plug can rattle under compression and create a ticking sound.

Exhaust Leak – A leaking manifold gasket or cracked exhaust flange can also emit a tick that mimics a lifter.

Direct Injection Injector Noise – On DI engines (post-2009), injectors seated in the combustion chamber can sound like valvetrain noise, particularly when under load.

How to Properly Diagnose Ticking in M96/M97 Engines

Jake’s recommendation is clear: Do not rely on compression or leak-down tests. These can both produce false positives or negatives.

✅ The correct method?

A borescope inspection, performed both through the spark plug hole and the sump, or using Jake’s hybrid third approach available to Rennvision subscribers.

🔗 Learn more about M96/M97 engine failure modes and solutions:

M96/M97 Engine Failures and Solutions (Part 1)

M96/M97 Engine Failures and Solutions (Part 2)

Final Thoughts: Assume Bore Scoring First

Jake Raby closes the video with a critical message:

“If you hear what sounds like a lifter tick, assume it’s bore scoring until proven otherwise.”

This mindset can save you from unnecessary repairs, financial loss, or worse—losing a car to an unrecoverable engine failure.

Whether you're a buyer, seller, technician, or enthusiast, recognizing the symptoms and insisting on a borescope inspection could be the difference between peace of mind and a $14,000 mistake.

📌 Key Takeaways:

Bore scoring is often misdiagnosed as lifter tick in M96/M97 engines.

Lifter failures typically cause misfires, not ticking.

Compression and leak-down tests are unreliable for diagnosing scoring.

Always confirm with a borescope inspection through spark plug holes and/or sump.

Porsche 997.1 vs 997.2: Key Differences, Common Problems, and What You Need to Know

If you’re shopping for a Porsche 997 or currently own one, understanding the differences between the 997.1 (2005–2008) and 997.2 (2009–2012) models is essential—especially when it comes to reliability, performance, and long-term maintenance.

While the interior and exterior changes between generations are subtle, the drivetrain updates introduced with the 997.2 are where Porsche made the most significant improvements. Let’s dive into what changed and what you should watch for in both generations.

🔧 Engine Updates: From M97 to MA1

The biggest change in the 997.2 is the introduction of the MA1 engine—also referred to as the 9A1. This engine replaced the problematic M97 engine found in the 997.1 and brought a number of advancements:

No IMS bearing – The intermediate shaft was eliminated.

Direct Fuel Injection (DFI) – Enabled higher compression, better performance, and improved fuel economy.

⚙️ Transmission: Tiptronic vs PDK

The 997.1 used the aging Tiptronic automatic transmission, which was replaced in the 997.2 by Porsche’s PDK dual-clutch gearbox. The result?

Faster shifts

Better performance

Improved fuel efficiency—even over manual transmission models

While the PDK is generally reliable, parts availability is limited. Porsche often recommends complete gearbox replacement when failures occur, making preventative maintenance crucial.

🚨 Common Issues with the 997.1

If you're considering a 997.1 model, be aware of these known issues:

IMS Bearing Failure

2005–2008 models had an updated, but still failure-prone, IMS bearing.

In 2006, Porsche introduced a larger non-serviceable IMS bearing. These are more robust but still benefit from having the factory grease seal removed to improve longevity.

Cylinder Bore Scoring

Affects both 3.6L and 3.8L engines.

Bore scoping and used oil analysis are the best ways to detect scoring before it becomes catastrophic.

Shared Problems with 996 Models

Coolant leaks, AOS failures, RMS leaks, and cracked expansion tanks are common.

⚠️ Known Issues in the 997.2

While the 997.2 resolved many of the issues found in earlier models, it’s not without its concerns:

Bore Scoring

Still possible, although far less common than in 997.1 models.

Coolant Crossover Pipe Leaks

Corroded metal connectors and aging rubber hoses can cause leaks as the car ages.

High-Pressure Fuel Pump Failure (HPFP)

A failed HPFP can result in limp mode or the car not starting.

Replacement pumps are costly and can be difficult to source.

PDK Transmission Issues

Failures in sensors, solenoids, or the valve body are rare but expensive.

Track use or poor service can accelerate wear.

🛢️ Oil System Differences

997.1 Models

Prone to oil starvation and aeration during track use.

Adding a deep sump is strongly recommended to improve oil control.

997.2 Models

Feature a variable output oil pump that solves many oiling issues.

However, fuel dilution from DFI is a new challenge.

Use Driven DI40 and change your oil every 6 months or 5,000 miles to reduce wear and prevent bore scoring.

🧰 Final Advice for Owners and Buyers

Annual inspections by a Porsche specialist are essential for both generations.

If you’re shopping for a 997.1 or 997.2, invest in a pre-purchase inspection (PPI). It can save you thousands in surprise repairs.

Be proactive—issues like bore scoring, coolant leaks, and HPFP failure are easier to deal with when caught early.