Denso 4046 Spark Plug

Denso 4046 U-Groove Spark Plug

Denso 4046 is a conventional spark plug built with a U-groove ground electrode to improve ignitability and support more efficient combustion. It uses a copper core center electrode with nickel tip materials for dependable secondary ignition performance in the right application.

Key Features

• U-groove ground electrode tip design for improved spark exposure
• Conventional spark plug construction for standard ignition systems
• Copper core center electrode for stable heat transfer
• Nickel center and ground electrode tip materials
• Pre-gapped to 0.7 mm
• 14.00 mm thread diameter, 19.00 mm reach, flat seat
• Manufacturer heat range 27
• Cross-reference: DENSO Auto Parts W27ES-U

Product Details

This Denso spark plug part number 4046 is engineered around a U-groove ground electrode, a design that increases the spark’s exposure area for more reliable ignition in the correct engine application. The copper core and nickel electrode materials support consistent operation, while the 20.6 mm hex size and flat seat help match OE-style service requirements. For buyers searching for Denso 4046 spark plug, W27ES-U replacement, or a Denso U-groove conventional plug for ignition service, this part is built for straightforward secondary ignition maintenance.

Compatible With select Denso applications and vehicle-specific ignition service needs, including Denso 4046 and W27ES-U cross-reference searches. If you are sourcing a Denso spark plug for a vehicle application that calls for this heat range, thread size, and reach, 4046 is the part number to verify against the catalog.

What It Helps Address

• Hard starting caused by worn or inefficient spark plugs
• Misfire concerns related to weak spark delivery
• Rough idle from degraded ignition performance
• Reduced combustion efficiency in the specified application
• Service replacement for a worn Denso 4046 or W27ES-U plug

Installation Notes and Tips

Verify thread diameter, reach, seat type, heat range, and pre-gap before installation. Confirm the engine calls for a 14.00 mm, 19.00 mm reach, flat-seat plug with a 0.7 mm gap and 27 heat range. Use proper spark plug service procedures and torque specifications from the vehicle manufacturer. For fitment-based searches, confirm the exact application before ordering Denso 4046.

Quality Assurance

Denso manufactures ignition components to OE-level specifications for the listed design and dimensional requirements. This part number 4046 follows the brand’s conventional U-groove spark plug format and is identified by Denso Auto Parts W27ES-U for cross-reference verification.