Denso 3013 Spark Plug

Denso 3013 U-Groove Spark Plug

The Denso 3013 is a conventional spark plug built for steady ignition performance in a wide range of classic and older applications. Its U-Groove ground electrode design is engineered to improve ignitability, helping support more efficient combustion in engines that call for a standard copper-core plug.

Compatible With Land Rover Defender 90, Discovery, and Range Rover applications, as well as select Toyota Land Cruiser, Mercedes-Benz 560-series, Dodge, Cadillac, Jeep, and Pontiac models, this plug is a direct-fit service part for many vintage secondary ignition setups. The Denso 3013 is also cross-referenced to Denso Auto Parts W14EXR-U for the same application.

Key Features

• U-Groove ground electrode tip design for improved ignitability
• Conventional spark plug construction for standard ignition systems
• Copper center electrode core material for dependable heat transfer
• Nickel center and ground electrode tip materials
• 5000 ohm resistance
• 0.8 pre-gap size
• Flat seat design
• 14 mm thread diameter, 19.00 mm reach, 20.6 mm hex size
• Manufacturer heat range 14

Product Details

Denso U-Groove Conventional spark plugs are built around a ground electrode shape that exposes the spark more effectively than a standard flat design. That can improve ignition consistency in engines that rely on a conventional plug specification. With a copper core center electrode and nickel electrode materials, the Denso 3013 is suited to older vehicles that require a standard-resistance plug with a flat seat and the listed thread and reach dimensions. This part number is commonly searched for Land Rover Range Rover, Toyota Land Cruiser, and Mercedes-Benz 560SEL service applications, and it is also referenced in classic Dodge, Cadillac, Jeep, and Pontiac fitments.

What It Helps Address

• Hard starting caused by worn or inefficient spark plugs
• Rough idle from inconsistent ignition firing
• Misfire symptoms related to aged secondary ignition components
• Reduced combustion efficiency in older engine setups
• Service replacement needs for vehicles calling for the specified plug dimensions

Installation Notes and Tips

Verify thread diameter, reach, seat type, heat range, and pre-gap before installation. The Denso 3013 uses a flat seat and 14 mm thread with a 19.00 mm reach, so it should be matched to the engine specification exactly. Check the ignition system condition, inspect plug wires or coil components, and confirm the gap setting against the vehicle service manual before final tightening.

Quality Assurance

Denso manufactures this plug as part of its U-Groove Conventional line, a product line focused on standard replacement ignition service with an emphasis on improved ignitability. The Denso 3013 is built to meet the listed OE-style specifications for the confirmed applications.