Ignition Coil & Iridium Spark Plugs for Toyota 4Runner (2003-2009) 4.0L V6

High-Output Ignition Coil & Iridium Spark Plugs for 2003-2009 Toyota 4Runner (1GR-FE / N210)

Restores ignition efficiency and eliminates misfires: Replaces degrading factory ignition coils and worn spark plugs with high-output coils and performance iridium plugs to ensure complete combustion and reliable spark delivery.

The Stock 4Runner Ignition Degradation

The OEM ignition coils on the 4.0L 1GR-FE engine are susceptible to thermal degradation over extended mileage. Prolonged exposure to under-hood temperatures and repeated thermal cycling breaks down the internal epoxy potting and primary winding insulation. This thermal fatigue leads to voltage leaks, weak spark, and intermittent misfires under load. Furthermore, factory copper or standard platinum spark plugs experience accelerated electrode erosion, increasing the spark gap over time. This widened gap strains the aging coils further, resulting in sluggish throttle response, reduced fuel economy, and potential unburnt fuel passing into the exhaust stream.

The Engineering Solution

This comprehensive ignition service kit bundles six high-energy ignition coils and six premium iridium spark plugs to completely overhaul the N210 ignition system. The upgraded coils feature enhanced copper wire windings and high-dielectric epoxy resin to resist heat soak and prevent voltage breakdown, ensuring a consistent, high-voltage spark output even during heavy towing or off-road loads. The included iridium spark plugs utilize an ultra-fine wire center electrode, which requires less firing voltage while maintaining an incredibly stable spark gap over a significantly longer service life compared to standard plugs. Together, this optimized spark delivery ensures complete fuel burn, restoring lost horsepower and torque, stabilizing idle, and maximizing overall engine reliability.

Technical Specifications

Compatibility

• 2003 Toyota 4Runner 4.0L V6
• 2004 Toyota 4Runner 4.0L V6
• 2005 Toyota 4Runner 4.0L V6
• 2006 Toyota 4Runner 4.0L V6
• 2007 Toyota 4Runner 4.0L V6
• 2008 Toyota 4Runner 4.0L V6
• 2009 Toyota 4Runner 4.0L V6

The Toyota Durability Standard

Designed to withstand the rigorous demands of overland trails and heavy towing duties, this ignition upgrade restores the consistent torque and legendary reliability expected from the 4th generation 4Runner.