The 2018 Honda Accord uses iridium-tipped spark plugs, with the exact part number and gap depending on which engine you have. The car was offered with two turbocharged options, and both typically use iridium plugs from NGK or Denso. Double-check the owner's manual or a Honda parts lookup for your VIN to confirm the precise specification.
Engine options and plug types
The 2018 Accord was available with two turbocharged engines. While both configurations generally use iridium plugs, the exact heat range, thread size, and gap can vary by engine. The guidance below covers the two common configurations:
- 1.5L turbocharged engine (L15B7) — Iridium-tipped spark plugs. Use OEM-equivalent plugs from NGK or Denso; a typical gap is around 0.043 inches (1.1 mm). Verify the exact part number for your model.
- 2.0L turbocharged engine (K20C1) — Iridium-tipped spark plugs. Use OEM-equivalent iridium plugs with a similar gap around 0.043 inches (1.1 mm). Confirm the correct heat range and thread size for your vehicle.
In practice, both engines rely on iridium plugs compatible with Honda’s DOHC design, with installation specifications (gap, torque, and heat range) documented in the owner’s manual or service bulletin. Always confirm the precise specification for your VIN.
How to choose and install spark plugs
To ensure you select the right plugs and install them correctly, follow these steps:
- Check your engine code and VIN to confirm the exact spark plug specification for your car.
- Choose an OEM-equivalent iridium plug from NGK or Denso that matches the engine’s heat range and thread size.
- Set the electrode gap to the recommended specification in the manual (commonly around 0.043 inches or 1.1 mm for the 2018 Accord turbo engines).
- Torque the plugs to the manufacturer specification using a proper torque wrench, and re-torque after the engine has cooled if required by the service data.
- Replace plugs in sets (both sides or all four cylinders) to maintain even ignition and avoid misfires.
Proper installation helps ensure smooth starts, good fuel economy, and long plug life. Always refer to Honda’s service data for your exact torque, heat range, and gap values for your model.
Where to source parts and part numbers
Because plug part numbers vary by engine and market, use a trusted parts lookup with your VIN to get the exact match. In general, you can choose OEM-equivalent iridium plugs from NGK or Denso:
- NGK Iridium IX plugs or other NGK OEM-equivalents suitable for Honda 1.5L and 2.0L turbo engines.
- Denso Iridium Power plugs or other Denso OEM-equivalents suitable for Honda 1.5L and 2.0L turbo engines.
When buying, provide your VIN and engine code to ensure you receive the correct heat range, thread size, and reach. Markets may use different part numbers, so a precise parts lookup is essential.
Summary
The 2018 Honda Accord uses iridium-tipped spark plugs, with the exact part number and gap determined by engine variant (1.5L or 2.0L turbo). Opt for OEM-equivalent iridium plugs from NGK or Denso, verify the gap in the owner’s manual, and follow proper installation torque. A VIN-based parts lookup is the best way to ensure you purchase the correct spark plugs for your specific car.