Denso 3212 Spark Plug

Denso 3212 U-Groove Spark Plug

The Denso 3212 is a conventional spark plug built for older import and compact truck applications that call for a flat-seat, 14 mm plug with a 19.00 mm reach. Its U-Groove ground electrode design improves ignitability for more consistent combustion and better engine efficiency in the right application.

Compatible With select Honda Accord, Honda Prelude, Honda Civic, Mitsubishi Galant, Nissan Maxima, and other listed vehicles, this plug is a direct-fit service part for many 1977-1994 applications. The Denso U-Groove Conventional line focuses on dependable secondary ignition performance with OE-style construction.

Key Features

• Part number: 3212
• U-Groove ground electrode tip design for improved spark exposure
• 5000 ohm resistor for noise suppression in ignition systems
• Copper center electrode core for stable heat transfer
• Nickel center and ground electrode tip materials
• Flat seat design with 14.00 mm thread diameter
• 19.00 mm reach and 20.6 mm hex size
• Manufacturer heat range: 20
• Pre-gapped to 1.1 mm

Detailed Description

Denso U-Groove Conventional spark plugs are built around a ground electrode shape that exposes more of the spark kernel to the air-fuel mixture. On the Denso 3212, that design is paired with a copper-core center electrode, nickel electrode materials, and a 5000 ohm resistor to support steady ignition performance in older carbureted and fuel-injected engines. This plug is a practical choice for service on vehicles such as the 1987-1989 Honda Accord, 1984-1987 Honda Prelude, and 1982-1984 Nissan Maxima, as well as other listed Mitsubishi, Isuzu, Subaru, Chevrolet, Dodge, and Nissan applications.

This part cross-references DENSO Auto Parts W20EXR-U11 and Honda 98079-561-46 for the same application.

What This Spark Plug Helps Address

• Hard starting caused by worn or fouled plugs
• Rough idle from weak or inconsistent spark delivery
• Misfire complaints under load or during acceleration
• Reduced fuel efficiency related to ignition wear
• Maintenance replacement for aging secondary ignition components

Installation Notes and Tips

• Verify thread diameter, reach, seat type, and heat range before installation.
• Confirm the gap specification against the vehicle service manual; this plug is pre-gapped to 1.1 mm.
• Inspect ignition wires, distributor components, and coil condition during spark plug service.
• Use proper torque procedures for flat-seat spark plugs to help prevent sealing issues.
• Check the vehicle-specific fitment list carefully for year, make, and model coverage.

Quality Assurance

Denso manufactures this U-Groove Conventional spark plug as a service replacement for a wide range of older Asian and domestic applications. The design uses OE-style materials and dimensions to support reliable ignition performance in the listed vehicles.