NGK Iridium IX Spark Plug Box of 4 (CPR7EAIX-9) - 9198

The NGK Iridium IX Spark Plug CPR7EAIX-9 (SKU 9198) is a fine-wire iridium plug sold in a box of 4, engineered for drivers who want crisper throttle response, stronger ignitability, and long-term reliability from their ignition system. Built on NGK's Iridium IX platform, this plug uses an ultra-fine iridium center electrode to deliver a more consistent spark and better anti-fouling performance than standard copper or platinum plugs, making it a popular upgrade for both daily-driven and performance-oriented engines.

Key Features & Benefits

• Fine-wire iridium center electrode — concentrates voltage for a stronger, more efficient spark that helps improve acceleration and throttle response.
• Exceptional anti-fouling design — the iridium construction resists deposit buildup better than traditional electrodes, supporting a cleaner, more consistent burn over time.
• Built for durability — iridium's hardness allows the fine-wire tip to hold its shape and performance characteristics longer than softer electrode materials, which is reflected in NGK's extended service-life expectations for this series.
• Consistent ignitability — designed specifically with the performance enthusiast in mind, helping maintain reliable combustion across a range of driving conditions.
• Sold as a complete box of 4 — convenient for a full ignition service on most 4-cylinder applications, or to keep spares on hand for larger engines.

Specifications

• Brand: NGK
• Series: Iridium IX
• Part Number: CPR7EAIX-9
• NGK Stock Number: 9198
• Thread Diameter: 10.0 mm
• Thread Reach: 19 mm
• Hex Size: 16 mm
• Quantity: Box of 4 spark plugs

Fitment

The NGK CPR7EAIX-9 (9198) is a specific heat-range, thread-diameter, and reach combination used across a range of applications that call for this exact plug designation. Because many different vehicles can share this spark plug, we recommend confirming the CPR7EAIX-9 part number against your vehicle owner's manual, factory service documentation, or by cross-referencing your original equipment spark plug before ordering. If your application calls for a different thread diameter, reach, or heat range, a different NGK part number will be required.

What's in the Box

• 4x NGK Iridium IX Spark Plug, part number CPR7EAIX-9 (stock number 9198)

Why Buy from ThreePiece.us

ThreePiece.us offers free shipping on every order and flexible financing through Affirm, making it easy to get the right ignition parts without delay. If you're unsure whether the CPR7EAIX-9 is the correct spark plug for your engine, our team can help you confirm specs like thread diameter, reach, and heat range before you order, so you get the right plug the first time.

Frequently Asked Questions

Q: How many spark plugs come in this listing?
A: This listing includes a box of 4 NGK Iridium IX spark plugs (CPR7EAIX-9 / stock number 9198).

Q: What makes Iridium IX different from a standard copper spark plug?
A: The Iridium IX series uses a fine-wire iridium center electrode instead of a standard copper electrode, which NGK designs to improve ignitability, anti-fouling resistance, and overall durability.

Q: How do I know if CPR7EAIX-9 is the right plug for my vehicle?
A: Check your vehicle's owner's manual or factory-specified spark plug part number, or compare the original plug's thread diameter (10.0 mm), reach (19 mm), and hex size (16 mm) against this listing before ordering.

Q: Can I order just one spark plug instead of the full box?
A: This product is sold as a complete box of 4 spark plugs.