Ignition Coil and Iridium Spark Plugs for Toyota Highlander (2008-2010) 3.3L

Direct-Fit Ignition Coil and Iridium Spark Plug Service Kit for 2008-2010 Toyota Highlander

What it Does: Replaces degraded factory coil packs and worn spark plugs with high-dielectric coil-on-plug assemblies and precision iridium plugs to restore proper combustion efficiency and eliminate misfires.

The Stock Highlander Ignition Breakdown

The transverse-mounted 3.3L V6 places the rear bank of ignition coils directly against the firewall, trapping radiant engine heat in a confined space. Over extended thermal cycles, the factory epoxy insulation and internal copper windings degrade, resulting in secondary voltage leakage, intermittent cylinder misfires under load, and carbon tracking along the plug boot. Combined with worn factory electrodes widening the spark gap, this breakdown forces the ignition system to demand higher primary voltage, leading to poor cold-start combustion, hesitations during hybrid-to-ICE transitions, and unburned fuel entering the catalytic converters.

The Engineering Solution

This complete ignition kit features six reinforced coil-on-plug units engineered with high-conductivity oxygen-free copper windings and high-grade silicone boots to resist thermal breakdown and dielectric puncture. Matched with six laser-welded iridium spark plugs, the fine-wire center electrode design lowers the required breakdown voltage while providing superior erosion resistance compared to standard copper or platinum alternatives. Solid brass terminal connections prevent internal corrosion, ensuring instantaneous spark delivery and consistent flame front propagation across the entire RPM range.

Technical Specifications

Compatibility

• 2008 Toyota Highlander Hybrid 3.3L V6 (3MZ-FE)
• 2008 Toyota Highlander Hybrid Limited 3.3L V6 (3MZ-FE)
• 2009 Toyota Highlander Hybrid 3.3L V6 (3MZ-FE)
• 2009 Toyota Highlander Hybrid Limited 3.3L V6 (3MZ-FE)
• 2010 Toyota Highlander Hybrid 3.3L V6 (3MZ-FE)
• 2010 Toyota Highlander Hybrid Limited 3.3L V6 (3MZ-FE)

The Toyota Reliability Standard

Engineered to withstand the demanding stop-start drive cycles of Toyota hybrid powertrains, these ignition components maintain precise arc timing and zero misfire tolerances to preserve smooth electric-to-gas power delivery and protect catalytic converter life.