2025 Tesla Model S Spark Plug Type & Gap

Quick reference

Why the right plug matters

For most gasoline-powered vehicles, selecting the correct spark plug is crucial for optimal engine performance, fuel efficiency, and emissions. Key factors include the plug's heat range, electrode material, and gap.

• Heat Range: A spark plug's heat range determines how much heat it dissipates. A plug that's too "cold" can lead to fouling, while one that's too "hot" can cause pre-ignition and engine damage.
• Electrode Metal: Different materials offer varying levels of durability and performance:
  • Iridium: The hardest and most durable automotive spark plug material, offering the longest lifespan (typically 100,000 miles or more) and excellent performance.
  • Platinum: A long-lasting material (around 60,000-80,000 miles) that provides good performance.
  • Copper: The most conductive and least expensive material, but also the least durable (requiring replacement every 30,000 miles or less).
• Gap: The space between the center and ground electrodes. An incorrect gap can lead to misfires, reduced power, and poor fuel economy.

How to gap a spark plug

Spark plug gapping is generally a straightforward process. You'll need a spark plug gapping tool, which can be a coin-style or wire-type gauge.

1. Check the gap: Use the gauge to measure the current gap. If it's within specifications, no adjustment is needed.
2. Adjust the gap (if necessary): If the gap is too small, carefully bend the ground electrode outwards with the gapping tool. If it's too wide, gently tap the ground electrode on a hard surface to close the gap. Always be gentle to avoid damaging the delicate electrode tip.

Replacement procedure tips

For cars that have spark plugs, the replacement procedure typically involves:

1. Accessing the plugs: This usually means removing the engine cover and disconnecting coil-on-plug (COP) units or spark plug wires from a distributor or coil pack.
2. Removing old plugs: Use a spark plug socket and ratchet to carefully unscrew the old plugs.
3. Installing new plugs: Hand-tighten the new plugs first to avoid cross-threading, then use a torque wrench to tighten them to the manufacturer's specifications.

Anti-seize and Dielectric Grease Debate

• Anti-seize: There's a debate about using anti-seize on spark plug threads. Some manufacturers advise against it, as it can alter torque readings and lead to over-tightening. If used, apply a very thin coat and reduce the torque spec by a small percentage.
• Dielectric Grease: Apply a small amount of dielectric grease inside the spark plug boots. This helps to seal out moisture, prevents corrosion, and makes it easier to remove the boots in the future.

Known issues

Specific known issues related to spark plugs typically arise in gasoline engines. For example, some Ford 3-valve engines from the mid-2000s were notorious for two-piece spark plugs that would break during removal, requiring special tools and techniques to extract the broken portions. Similarly, certain GM 5.3L engines utilized ionization-sensing coils, where spark plug condition could directly impact the ignition system's ability to detect ionization in the combustion chamber.

Conclusion

The 2025 Tesla Model S is an all-electric vehicle. As such, it does not use spark plugs, nor does it have a conventional internal combustion engine requiring them. Its propulsion system relies on electric motors and a high-voltage battery. Therefore, the discussions about spark plug types, gaps, torque, and replacement intervals do not apply to this vehicle.

Need plugs replaced? Find a shop on Repairius.