NGK 4291 Spark Plug

NGK V-Power Spark Plug 4291 Overview

NGK V-Power Spark Plug 4291 is an OE-style replacement spark plug built for consistent ignition performance in a wide range of domestic and import applications. It uses a copper core center electrode, nickel tip materials, and a standard ground electrode design to support reliable combustion and stable engine operation.

Compatible With BMW 550i, BMW 650i, BMW X5, Honda Civic, and Dodge Ram applications where the listed OE-style gap and heat range apply. The NGK 4291 is also referenced by part number ZFR6F-11.

Key Features

• Brand: NGK V-Power Spark Plug
• Part number: 4291
• OE-style design for domestic and import vehicle service
• Copper core center electrode for efficient spark delivery
• Nickel center and ground electrode tip materials
• Standard ground configuration with one ground electrode
• Pre-gapped at 0.044 inches
• 5,000 ohm resistance
• 14 mm thread diameter, 0.75 inch reach, flat seat
• 5/8 inch hex size and non-removable nut terminal

Product Details

NGK builds this V-Power spark plug to meet original equipment standards for durability and operational consistency. The copper core helps promote dependable ignition response, while the standard ground electrode layout supports steady spark exposure across a broad range of service applications. With a manufacturer heat range of 6 and a 0.044 inch pre-gap, this plug is specified for vehicles that call for that exact setup, including select BMW 550i, BMW 650i, BMW X5, Honda Civic, and Dodge Ram models.

This part cross-references Champion Spark Plug 412 and 436 for the same application.

Common Uses

• Rough idle caused by worn or fouled spark plugs
• Hard starting or extended crank time
• Misfire codes related to weak ignition output
• Reduced fuel economy from degraded spark performance
• Loss of throttle response under load

Installation Notes

Verify the vehicle’s OE specification before installation and adjust the spark plug gap to 0.044 inches where required by the application. Confirm thread diameter, reach, seat type, and heat range match the engine specification. Use proper torque procedures during installation and inspect ignition components such as coils and wires when servicing the plugs.

Fits 2006-2010 BMW 550i, N/A; Fits 2006-2010 BMW 650i, N/A; Fits 2004-2010 BMW X5, N/A; Fits 2001-2005 Honda Civic, N/A; Fits 1997-2003 Dodge Ram 1500, N/A.

Quality Assurance

NGK is a long-established OE supplier and manufacturer with extensive coverage across automotive, motorcycle, marine, and small engine applications. The brand’s North American manufacturing and distribution network supports consistent product availability and OE-level production standards.