NGK 3657 Spark Plug

NGK Laser Iridium Spark Plug 3657

NGK Laser Iridium Spark Plug 3657 is an OE-style ignition component built for precise combustion performance and long service life. This spark plug uses an iridium center electrode, nickel ground electrode, and a 0.044 in pre-gap to match the listed factory specifications for select Honda, Acura, and Saturn applications.

The NGK Laser Iridium Spark Plug line focuses on original-equipment fit and consistent ignition performance. Part number 3657, also identified as IZFR5K11, is specified for vehicles that call for a flat seat, 14 mm thread diameter, 0.75 in reach, and 5/8 in hex.

Key Features

• Laser Iridium spark plug with iridium center electrode tip material
• 0.044 in pre-gap for OE-specified applications
• 5,000 ohm resistance for ignition system compatibility
• Flat seat design with 14 mm thread diameter and 0.75 in reach
• Trapezoid ground electrode tip design with standard ground configuration
• NGK part number 3657 / IZFR5K11

Vehicle Fitment

• Fits 2005-2010 Honda Odyssey, N/A. Spark Plug Gap is 0.044 inches per OE specifications; Laser Iridium Spark Plug.
• Fits 2006-2008 Honda Pilot, N/A. Spark Plug Gap is 0.044 inches per OE specifications; Laser Iridium Spark Plug.
• Fits 2006-2008 Honda Ridgeline, N/A. Spark Plug Gap is 0.044 inches per OE specifications; Laser Iridium Spark Plug.
• Fits 2004-2007 Saturn Vue, N/A. Gap 0.044"; OE Equivalent Design; 100,000 mile OE Manufacturer Recommended Service Interval; Laser Iridium Spark Plug.
• Fits 2003-2006 Acura MDX, N/A. Gap 0.044"; OE Manufacturer recommends service interval every 105,000 miles; Laser Iridium Spark Plug.

Detailed Description

NGK 3657 is a Laser Iridium spark plug engineered for vehicles that require a precise OE-style ignition setup. The iridium center electrode supports stable spark delivery, while the nickel ground electrode and trapezoid tip design align with factory-style combustion requirements. For drivers servicing a Honda Odyssey, Honda Pilot, Honda Ridgeline, Saturn Vue, or Acura MDX, this plug matches the listed gap, seat type, reach, and thread dimensions called out in the fitment data.

This part cross-references DENSO Auto Parts 5628 for the same application.

Common Issues This Part Helps Address

• Rough idle caused by worn spark plugs
• Hard starting from weak ignition output
• Misfire conditions tied to incorrect plug gap or electrode wear
• Reduced fuel economy from inconsistent combustion
• Loss of throttle response related to degraded spark performance

Installation Notes and Tips

Verify the engine application before installation and confirm the plug gap matches the OE specification of 0.044 in. Use the correct 5/8 in hex socket and install to the manufacturer’s torque specification for the cylinder head material. Check the existing ignition system condition, including coils and wires where applicable, so the new plug can perform as intended.

Quality Assurance

NGK is a long-established OE supplier and manufacturer of spark plugs for domestic and import vehicles in North America. Its manufacturing and distribution network supports OE-level standards for durability and operational performance across a wide range of automotive applications.