NGK 5685 Spark Plug

NGK Standard Spark Plug for OE-Style Ignition

NGK Standard Spark Plug 5685 is built for drivers who want a direct-replacement spark plug with OE-style construction and consistent ignition performance. This NGK spark plug uses a copper core center electrode, nickel tip materials, and a 5,000 ohm resistor to support stable spark delivery in everyday driving.

Compatible With select Audi and Mitsubishi applications, including 1987-2002 Mitsubishi Mirage, 1987-1992 Audi 80, 1988-1992 Audi 80 Quattro, 1988-1991 Audi 90 Quattro, 1987-1988 Audi 5000 Quattro, and 1989-1991 Audi 100 and 100 Quattro. Part number BPR5EKU is also identified by stock number 5685.

Key Features

• NGK Standard Spark Plug line for OE-style replacement service
• Copper core center electrode for efficient heat transfer
• Nickel center and ground electrode tip materials
• 5,000 ohm resistor for ignition noise suppression
• Semi-surface discharge ground configuration with two ground electrodes
• Pre-gapped at .028 inch with a flat seat design
• 14 mm thread diameter, .75 inch reach, and 13/16 inch hex size
• Heat range 5 for specified engine applications

Product Details

NGK has long supplied original equipment spark plugs for domestic and import vehicles, and the Standard Spark Plug line focuses on dependable everyday service with OE-equivalent design details. This BPR5EKU spark plug is engineered with a removable nut terminal, nickel ground electrode core material, and a semi-surface discharge ground electrode tip design to support consistent combustion in the applications listed. For shoppers searching for NGK 5685 spark plug, BPR5EKU replacement, or an OE-style spark plug for Audi 80, Audi 100, or Mitsubishi Mirage, this part matches the specified fitment and service requirements.

This part cross-references Monroe Shocks & Struts (e.g., 5685) for the same application.

What It Helps Address

• Hard starting caused by worn or fouled spark plugs
• Rough idle from inconsistent spark delivery
• Misfire conditions related to aged ignition components
• Reduced fuel economy from inefficient combustion
• Weak throttle response in specified Audi and Mitsubishi engines

Installation Notes and Tips

Verify the engine calls for NGK BPR5EKU / 5685 before installation. Confirm the plug gap against the vehicle service specification, since some listed applications note a .032 inch gap requirement while the plug is pre-gapped at .028 inch. Check thread reach, seat type, and hex clearance during service, and follow the manufacturer’s torque specification for the engine.

Quality Assurance

NGK is a major OE spark plug supplier with extensive North American and global manufacturing and distribution support. The Standard Spark Plug line is built to maintain original equipment standards for durability and operational performance in the listed applications.