NGK 94631 Spark Plug

NGK Iridium IX Spark Plug for Lexus Applications

NGK Iridium IX Spark Plug 94631 is built for drivers who want precise ignition performance, stable idle quality, and strong throttle response. This performance spark plug uses an iridium fine-wire center electrode and a tapered cut ground electrode to support reliable starting and consistent combustion in select Lexus models.

Key Features

• Iridium fine-wire center electrode for durable spark delivery
• Taper cut ground electrode for improved starting, idling, and throttle response
• Fine-wire design supports extreme ignitability and anti-fouling performance
• Resistor type plug with 5,000 ohm resistance
• Flat seat, M14 x 1.25 thread, 5/8 in. hex
• Pre-gapped at .032 in. / 0.8 mm
• Heat range 7 with ceramic insulator construction

Product Details

Part number 94631 is part of NGK’s Iridium IX spark plug line, a performance-focused series engineered around iridium metallurgy and a fine-wire center electrode. The iridium center tip and platinum ground tip help support long service life, while the nickel ground electrode core and copper center core contribute to stable electrical performance. For Lexus IS300, RC300, NX300, GS300, GS200t, IS200t, NX200t, and RC200t applications, this plug is specified with a 0.036 in. gap in the fitment notes.

This part cross-references NGK LFR7AIX-PG and Toyota/Lexus OE reference 90919-01276 for the same application. The NGK 94631 is a direct-fit spark plug choice for drivers maintaining ignition performance on select Lexus turbo and naturally aspirated models.

What It Helps Address

• Hard starting or slow crank ignition response
• Rough idle caused by worn spark plugs
• Throttle hesitation during acceleration
• Misfire conditions related to degraded spark output
• Fuel economy loss from inefficient combustion

Installation Notes

Verify the specified gap before installation and follow the vehicle service procedure for torque and plug access. This plug uses a flat seat, non-removable nut terminal, and 5/8 in. hex, so use the correct spark plug socket and ignition service tools. Confirm application details for your Lexus IS300, RC300, NX300, GS300, GS200t, IS200t, NX200t, or RC200t before installation.

Quality Assurance

NGK is a recognized ignition component manufacturer, and the Iridium IX line is built around durable iridium electrode construction and performance-oriented spark characteristics. Part number 94631 is engineered for consistent ignition service in the listed Lexus fitments.