NGK Iridium Spark Plugs CR9EIA9 4-Pack — Part 6289, Durable Long-Life Ignition

NGK 6289 CR9EIA9 is a four-pack of iridium-tipped spark plugs engineered to deliver reliable ignition and consistent combustion for compatible engines.

These NGK CR9EIA9 spark plugs (part number 6289) come packaged in sets of four and are designed to meet OEM fit and performance standards. They feature durable construction intended for stable firing, long service life, and ease of replacement. Whether you’re maintaining a vehicle, boat, ATV, or small engine that specifies CR9EIA9 plugs, this four-pack helps you swap all cylinders at once for consistent performance across the engine.

What makes the CR9EIA9 spark plugs suitable for regular maintenance?

The CR9EIA9 plugs are built with robust electrodes and materials designed to resist wear and maintain a consistent spark over time. Regular replacement helps preserve ignition efficiency and can reduce misfires caused by worn plugs. These plugs are sold in a four-pack so a complete multi-cylinder change is straightforward and cost-effective.

• Four plugs per package—change all cylinders at once.
• Durable electrode materials for extended service life.
• Manufactured to NGK tolerances for reliable fitment and gap retention.

How do I know if CR9EIA9 is the correct plug for my engine?

Consult your engine or vehicle owner’s manual, or cross-reference NGK part 6289 with the OEM part number list to confirm compatibility. Plug heat range, thread size, and reach must match your engine’s specifications to avoid performance or fit issues. When in doubt, use NGK’s online application tools or contact a mechanic for verification.

• Check owner’s manual for recommended NGK part numbers.
• Confirm thread size and reach match your cylinder head.
• Use NGK cross-reference or dealer lookup for precise fitment.

What installation tips improve longevity and performance?

Install new plugs with the correct gap and torque to prevent damage and ensure a good seal. Use a torque wrench to the manufacturer’s specification, apply anti-seize only if recommended, and clean the plug holes before fitting. Proper installation reduces the risk of cross-threading and ensures reliable spark delivery.

• Verify and set the plug gap per manufacturer specs.
• Tighten to specified torque—avoid over- or under-tightening.
• Replace ignition boots or coils as needed for full system reliability.

How often should these NGK spark plugs be replaced?

Replacement intervals vary by engine, driving conditions, and plug type; refer to your vehicle’s maintenance schedule for precise guidance. Iridium-type plugs like the CR9EIA9 often last longer than standard copper plugs but still require periodic inspection. Signs it’s time to replace plugs include rough idle, reduced fuel economy, and difficulty starting.

• Follow the engine manufacturer’s recommended interval.
• Inspect plugs during routine tune-ups or when performance drops.
• Replace all cylinders simultaneously for balanced operation.

Who is this for: The NGK 6289 CR9EIA9 4-pack is aimed at do-it-yourself mechanics, professional technicians, and owners of compatible vehicles or small engines who want OEM-quality replacement plugs in a convenient four-pack. It’s practical for anyone performing routine tune-ups, rebuilding engines, or servicing multi-cylinder machines that require CR9EIA9 spark plugs.