NGK 91899 Laser Iridium Spark Plug M12x1.25 Thread, 26.5 mm Reach

Vehicle Fitment

• Fits select Subaru 2.0L/2.5L naturally aspirated engines (e.g., Forester, Impreza, Crosstrek) from 2018 and newer - fitment beyond listed years should be verified.

Features

• Laser Iridium center electrode for outstanding durability and stable spark performance.

Specifications

• Part Number: 91899
• Thread Size: M12 x 1.25 mm
• Reach/Thread Length: 26.5 mm
• Seat Type: Crush washer (flat) seal
• Electrode Material: Iridium center tip
• Ground Electrode: Platinum or double fine-electrode style
• Resistance: Approx. 5000 Ω (resistor plug version)
• Spanner/Hex Size: 14 mm
• Use Type: OE replacement for compatible Subaru (and similar) engines

Included Components

• 1x NGK 91899 Laser Iridium spark plug

Product Description

The NGK 91899 Laser Iridium spark plug is designed to deliver precise ignition for late-model engines that demand high ignitability and long service life. Featuring a fine-wire iridium center electrode and durable construction, it serves as a premium direct replacement in applications where NGK specifies high-performance OE plugs.

With a thread size of M12 x 1.25 and a reach of 26.5 mm, this plug fits tightly in modern engine designs and ensures proper combustion chamber placement. The double fine electrode layout promotes efficient fuel burn and improved throttle response - especially useful for turbocharged or naturally aspirated vehicles with advanced ignition systems.

Installation is straightforward: ensure the original plug's thread, reach and seat type match. Use the appropriate torque spec, new crush washer, and allow the engine's control module to complete a full drive cycle. For best results, follow NGK (or vehicle manufacturer) service interval recommendations and swap plugs in sets when required.