2025 Honda Pilot Spark Plug Type & Gap

Quick reference

Why the right plug matters

Selecting the correct spark plug for your 2025 Honda Pilot's 3.5L V6 engine is crucial for optimal performance, fuel efficiency, and longevity. Spark plugs are available in various materials, each with unique characteristics:

• Iridium: These are the most common type for modern vehicles like your Pilot. Iridium is extremely hard and corrosion-resistant, allowing for very fine electrodes that produce a strong, focused spark. This leads to better fuel economy and a longer lifespan, typically 100,000 miles or more, which aligns with the recommended interval for your vehicle.
• Platinum: Platinum plugs offer good durability and performance, often lasting around 60,000 to 80,000 miles. They are a step up from traditional copper but generally not the OEM choice for vehicles designed for iridium.
• Copper: While excellent conductors of electricity, copper plugs have softer electrodes that wear down more quickly. They are typically found in older vehicles or high-performance applications where frequent changes are acceptable. They are not suitable for your 2025 Honda Pilot.

The "heat range" of a spark plug is another critical factor, indicating its ability to dissipate heat from the combustion chamber. A plug that's too "hot" (dissipates heat slowly) can lead to pre-ignition and engine damage, while one that's too "cold" (dissipates heat too quickly) can foul with carbon deposits. Your Pilot's OEM specified iridium plugs are designed with the perfect heat range for its engine.

How to gap a spark plug

Properly gapping a spark plug ensures the correct distance between the center and ground electrodes, which is vital for a strong, consistent spark. While many iridium plugs come pre-gapped, it's always a good idea to double-check, especially if you opt for aftermarket plugs. For your 2025 Honda Pilot, the recommended gap is 0.043 inches (1.1 mm).

To gap a spark plug:

1. Use a wire-type spark plug gapping tool: Flat disc-style gauges can damage the delicate iridium electrode.
2. Carefully measure the gap: Slide the appropriate wire gauge between the electrodes. It should have a slight drag.
3. Adjust if necessary: If the gap is too small, gently bend the ground electrode outward with the gapping tool's adjuster. If it's too wide, carefully tap the ground electrode on a clean, hard surface to close the gap slightly. Never bend the center electrode, especially on iridium plugs, as it can easily break!

Replacement procedure tips for the 3.5L V6 (J35Y8)

The 2025 Honda Pilot's 3.5L V6 engine utilizes a coil-on-plug ignition system, meaning each spark plug has its own individual ignition coil directly mounted on top of it. This eliminates traditional spark plug wires.

Here are some tips for replacing your spark plugs:

• Access: The coils and plugs on the front bank of cylinders are relatively easy to access. The rear bank, however, might require removing the intake manifold to gain adequate access. Refer to your Honda service manual for specific removal procedures.
• Coil-on-plug removal: Carefully disconnect the electrical connector from each ignition coil, then unbolt and gently pull the coil straight up and off the spark plug. Avoid twisting or prying, which can damage the coil or connector.
• Anti-seize debate: There's ongoing debate regarding the use of anti-seize on spark plug threads. For modern spark plugs with nickel-plated shells, manufacturers like NGK often advise against using anti-seize, as it can alter the torque readings and lead to over-tightening or issues with the plug's electrical grounding. Always follow the spark plug manufacturer's recommendations. If you do choose to use anti-seize, ensure it's a very thin coating and reduce the torque specification by about 10-20%.
• Dielectric grease on boots: Apply a small amount of dielectric grease inside the spark plug boot (the bottom portion of the coil that fits over the plug). This helps seal out moisture, prevents corrosion, and makes future removal easier. Be careful not to get any grease on the actual electrode or inside the coil's contact spring.
• Torque specs are critical: Always use a torque wrench to tighten spark plugs to the specified 13 lb-ft (18 Nm). Over-tightening can strip the cylinder head threads or crack the spark plug porcelain, while under-tightening can lead to insufficient heat transfer and potential misfires.

Known issues

At this early stage for the 2025 Honda Pilot, there are no widespread or well-documented systemic spark plug issues like the cracked porcelain on Ford 3-valve engines or broken plug shells seen in some older designs. Adhering to the recommended maintenance schedule and using the correct OEM or high-quality aftermarket spark plugs should ensure trouble-free operation.

Need plugs replaced? Find a shop on Repairius.