NGK 4294 Spark Plug

NGK Laser Iridium Spark Plug 4294 Overview

The NGK Laser Iridium Spark Plug 4294 is engineered for precision ignition performance in select BMW models. Designed to deliver reliable spark and efficient combustion, this spark plug supports optimal engine operation in vehicles like the BMW 550i, 650i, 750i, 750Li, and X5.

• Iridium center electrode tip for enhanced durability and ignition
• Copper core center electrode for improved conductivity
• Standard ground electrode with nickel core material
• Pre-gap size of 0.044 inches for precise spark gap
• Flat seat type with 14mm thread diameter and 0.75 inch reach
• Non-removable nut electrical terminal type
• Manufacturer heat range rating of 6
• Hex size of 5/8 inch for installation

About the NGK Laser Iridium Spark Plug Line

The Laser Iridium Spark Plug line from NGK combines iridium's high melting point with precise electrode design to provide consistent ignition and long service life. This product line focuses on delivering stable spark performance and durability, making it suitable for high-performance engines such as those found in BMW vehicles. The 4294 part number is a specific fitment within this line, tailored to meet the ignition requirements of select BMW models.

Technical Details and Features

The NGK 4294 spark plug features a copper core center electrode that enhances electrical conductivity, paired with an iridium tip that resists wear and maintains a sharp spark point. The ground electrode uses nickel core material with a standard design, ensuring reliable grounding and spark gap stability. The pre-gap size of 0.044 inches is factory set to optimize ignition timing and combustion efficiency. With a flat seat and 14mm thread diameter, this spark plug fits securely in the combustion chamber. The non-removable nut terminal type simplifies installation and connection reliability.

Compatible BMW Models and Applications

• BMW 550i
• BMW 650i
• BMW 750i and 750Li
• BMW X5

This spark plug is designed specifically for these BMW models, ensuring proper fitment and performance according to manufacturer specifications.

Common Issues Addressed by NGK 4294 Spark Plug

• Engine misfires due to worn or fouled spark plugs
• Reduced fuel efficiency from inconsistent ignition
• Difficulty starting the engine in cold conditions
• Rough idling or hesitation during acceleration
• Increased emissions from incomplete combustion

Installation Notes and Tips

Before installation, verify the spark plug gap is set to 0.044 inches as specified. Use a torque wrench to tighten the spark plug to the manufacturer’s recommended torque to avoid damage to the threads or seat. The 5/8 inch hex size allows for standard spark plug socket use. Ensure the ignition system is off and the engine is cool before replacing spark plugs. The non-removable nut terminal requires compatible ignition wire connectors for secure attachment.

Quality Assurance and Warranty

NGK spark plugs, including the Laser Iridium Spark Plug 4294, are manufactured to meet strict quality standards for durability and performance. While specific warranty details may vary, NGK products typically come with a limited warranty against manufacturing defects. Using OEM-quality spark plugs like the NGK 4294 helps maintain engine reliability and performance in your BMW vehicle.