MOTO1988 Ignition Coil & Spark Plug Kit for Honda TRX400EX 1999-2006 — OEM Fit, Improved Starting

This MOTO1988 ignition coil and spark plug kit replaces Honda OEM 30500-HN1-003 to restore reliable spark on Sportrax 400 TRX400EX models from 1999 through 2006.

If your Honda TRX400EX is showing weak starts, rough idle, or misfires, a worn ignition coil or fouled spark plug is often the cause. This package contains one ignition coil and one spark plug designed to fit the Sportrax 400 TRX400EX 2x4 across model years 1999–2006, making it a straightforward service part for routine tune-ups or troubleshooting ignition issues.

How will this coil and plug improve my ATV's starting and idle?

Replacing an old ignition coil and plug can deliver a stronger, more consistent spark, which helps the engine start faster and maintain a steadier idle. The kit matches the OEM part number to ensure electrical and mounting compatibility with the TRX400EX.

• Direct OEM compatibility: 30500-HN1-003 fitment reduces installation guesswork.
• Stronger spark output improves combustion efficiency and throttle response.
• One-coil, one-plug package for a targeted, budget-friendly repair.

Will this part fit my specific TRX400EX year and model?

This ignition coil and spark plug are intended for the Honda Sportrax 400 TRX400EX 2x4 from 1999 through 2006. Double-check your machine’s model year and OEM part number to confirm fit before purchasing.

• Confirmed coverage: TRX400EX 2x4 model years 1999–2006.
• OEM reference included: 30500-HN1-003 to match service manuals and parts diagrams.
• Check photos and listing details if your machine has aftermarket modifications.

What should I expect during installation and maintenance?

Installation is typically plug-and-play for stock TRX400EX wiring and mounts but basic mechanical skills and hand tools are recommended. Inspect connectors and wiring for corrosion and ensure proper spark plug gap per Honda specifications before final assembly.

• Simple replacement: bolt-on coil and standard spark plug thread and gap.
• Verify spark plug gap and torque to OEM values for reliable performance.
• Inspect ignition wiring harness and replace any damaged clips or boots when servicing.

What after-sales support and purchase tips are provided?

MOTO1988 advises buyers to confirm model fit with the applicable years and OEM number shown in the listing. If you encounter any issues during purchase or installation, customer support is available by email to assist with troubleshooting or warranty-related questions.

• Tip: Compare the OEM number 30500-HN1-003 with your existing coil before ordering.
• Support: Contact MOTO1988 via email for help with fitment or product concerns.
• Packaging: Kit includes 1 ignition coil and 1 spark plug for a focused repair.

Who is this for? This kit is intended for owners and mechanics of Honda Sportrax 400 TRX400EX 2x4 ATVs (1999–2006) who need a direct-replacement ignition coil and spark plug for routine maintenance, diagnosis of ignition-related issues, or restoring reliable starting and engine smoothness. It’s also suitable for riders performing a single-cylinder ignition refresh without buying a larger parts bundle.