How to Prevent Porsche Bore Scoring

How to Prevent Porsche Bore Scoring

Car engines contain a large number of components made from aluminum. In your modern watercooled Porsche engine, this includes the pistons and cylinders. Aluminum is lightweight and versatile, but it has its limitations. For decades, Porsche used a durable Nikasil plating for the wear surface of the aluminum cylinders that is not susceptible to cylinder bore scoring. For Boxster, Cayman, and 911 engines, Porsche chose to use hypereutectic Lokasil and Alusil engine blocks instead that have raw, uncoated aluminum bores. For this reason, over time, your Porsche may experience bore scoring or cylinder bore scoring.

What is Porsche Bore Scoring?

Which models are affected?

• Porsche 996 bore scoring
• Porsche 997 bore scoring
• Porsche 911 bore scoring
• Porsche 987 bore scoring
• Porsche Cayman bore scoring
• Porsche Boxster bore scoring (3.4 M97.22 engine only)

Consider that for an engine that has traveled 60,000 miles, each piston has gone up and down over 300 million times on average. If the required preventative maintenance as outlined below has not been carried out, serious damage and potentially engine failure can occur. The reason that taking the steps to prevent Porsche bore scoring is so important is that it can have extremely negative impacts on your car's performance and engine longevity. As the scoring worsens, the cylinders will lose their ring seal, and harmful contaminants will enter your oil as it bypasses the piston rings. Those contaminants can then be spread throughout to all the lubricated components in your Porsche's engine, eventually leading to catastrophic damage in the worst case scenario. It's far cheaper to take these steps to prevent Porsche cylinder bore scoring through preventative maintenance than wait to have a failure and have to rebuild or replace your Porsche engine.
 

Porsche Bore Scoring Preventative Maintenance

• Borescope your cylinders – It is an excellent idea to know the condition of the cylinder bores. Bore scoping your cylinders for Porsche bore scoring is critical, especially important if you are in the market for buying a new (to you) Porsche.
• Check your fuel trim and test for vacuum leaks – A Porsche technician with the proper diagnostic tools should be able to check fuel trim values to ensure they are within specification. A bad mass air flow sensor or oxygen sensors can also cause over-fueling that will wash down cylinders and lead to bore scoring, so these components, along with the AOS and associated vent lines, also need to be replaced as part of preventative maintenance to ensure your engine is running correctly. Vacuum leaks can also cause your engine to run rich, so having the engine smoke tested to check for leaks is highly recommended. The Durametric Porsche Diagnostic Tool can be used to check fuel trims as well as mass airflow and oxygen sensor values.
• Perform a manometer test - A healthy M96 or M97 engine should have a manometer reading 4.0-6.0" of H2O. Low manometer readings may indicate worn piston rings or poor ring seal. High manometer readings may indicate a faulty AOS. The CR Tools Porsche Crankcase AOS Vacuum Measurement Manometer Tool allows you to easily perform a manometer test on your Porsche engine.
• Purchase high quality gasoline – Choose Top Tier or ethanol free premium fuel for your Porsche to keep your fuel injectors as clean as possible. Dirty injectors can hurt cylinder and piston lubrication, leading to excessive wear.
• Maintain your fuel injectors – Use a bottle of Driven Injector Defender every other fill-up. We recommend replacing your fuel injectors every 75 thousand miles to eliminate the chance of leaky injectors washing down your cylinders that can lead to bore scoring. Having your original injectors cleaned rather than replacing with new ones is not recommended.
• Install a low temperature thermostat – A low temperature thermostat opens earlier and stays open where the factory thermostat can cycle open and closed during normal operation, causing the coolant to bypass the radiators and creating hot spots in the engine.
• Start out slowly until warm – Never let your Porsche engine idle to warm it up as the rich mixture during cold start can wash down cylinder bores just like a bad injector. It's important to start driving immediately but keep engine rpm below 3000 rpm and avoid running the engine at wide open throttle until the engine is at full operating temperature.
• Change oil at the recommended intervals – It's important to change your car's engine oil every 6 months or 5,000 miles using Driven DT40 or Driven DI40, as these oils are formulated with increased levels of Moly additives that most oils do not have, which in turn helps to protect the cylinder walls. If you track your car, drive short distances, or operate the engine in cold climates, more frequent oil changes may be necessary. Doing so will help the oil remain free of contaminants that could lead to Porsche cylinder bore scoring.
• Don't neglect your filters – Be sure to change your engine oil filter every time you change your Porsche's oil with a quality oil filter. Consider LN Engineering's Spin-on Oil Filter adapter, adding FilterMag oil filter magnet, and one of our Porsche magnetic engine oil drain plugs. Don't forget to replace your air and fuel filters as recommended by Porsche, only using Genuine, OEM filters, or filters recommended by LN Engineering.
• SPEEDiagnostix oil analysis – Conduct used oil analysis at every oil change to monitor for levels of abnormal wear levels or contamination in your engine oil. Even if you do not have any symptoms, the data you receive from the analysis could tell you if bore scoring is already occurring, or if there are contaminants in your oil that may accelerate the process such as excessive fuel dilution which may point to other problems with your engine that need immediate attention.

What if you already have Porsche bore scoring?

More info about LN Engineering solutions to prevent Porsche bore scoring and fix Porsche engines with scored cylinder bores.

Contact our team to help avoid Porsche cylinder bore scoring today!