Ignition Coil and Iridium Spark Plugs for Toyota Highlander (2017-2019) 3.5L

Direct-Fit Ignition Coil and Iridium Spark Plug Kit for 2017-2019 Toyota Highlander

What it Does: The Ignition Coil and Iridium Spark Plug Kit replaces fatigued coil-on-plug boots and eroded electrodes on the 2017-2019 Toyota Highlander to eliminate misfires, stabilize idle, and restore peak combustion efficiency.

The Stock Toyota Highlander Ignition Breakdown

Under the transverse engine packaging of the XU50 chassis, the 2GR-FKS 3.5L V6 traps substantial radiant heat around the firewall-facing rear cylinder bank (cylinders 1, 3, and 5). Over time, thermal cycling degrades the factory coil's dielectric resin and silicone boots, creating micro-fractures that induce voltage leakage and secondary winding breakdown. Combined with gradual electrode erosion on aged spark plugs, the widened plug gap overburdens the coils, resulting in sluggish throttle response, erratic idle, and diagnostic trouble codes from P0300 to P0306.

The Engineering Solution

This complete six-cylinder ignition service kit features pencil coils constructed with high-grade magnetic silicon steel cores and temperature-resistant epoxy compounds to resist thermal breakdown. Reinforced silicone spark plug boots insulate against flashover and high-voltage arc loss under heavy engine load. Paired with fine-wire iridium spark plugs that require lower firing voltage while offering superior thermal conductivity, this direct-fit kit maintains optimal flame kernel development for Toyota's combined port and direct-injection (D-4S) combustion system.

Technical Specifications

Compatibility

• 2017-2019 Toyota Highlander LE 3.5L V6
• 2017-2019 Toyota Highlander LE Plus 3.5L V6
• 2017-2019 Toyota Highlander XLE 3.5L V6
• 2017-2019 Toyota Highlander SE 3.5L V6
• 2017-2019 Toyota Highlander Limited 3.5L V6
• 2017-2019 Toyota Highlander Limited Platinum 3.5L V6

Frequently Asked Questions

Does this fit the XU50 Highlander?
Yes, this is a direct fit for the 2017-2019 Toyota Highlander equipped with the 2GR-FKS engine.

Are the included iridium spark plugs pre-gapped for the 2GR-FKS engine?
Yes, all six plugs arrive pre-gapped to factory tolerances for straightforward installation without gap manipulation.

The Toyota Durability Standard

The Highlander is engineered for dependable family transport and heavy hauling duty. Installing heat-resilient ignition components ensures clean burn efficiency under load, protects upstream catalytic converters from unburnt fuel damage, and maintains factory payload towing performance.