2022 Toyota Highlander — Spark Plug Type, Gap & Torque Specs

Quick reference

Note: Toyota sources both Denso and NGK laser iridium plugs as OE. Always confirm the exact part number on your under-hood emissions label or by VIN with a Toyota parts desk.

Why the right plug matters

• Heat range: Using the specified heat range keeps the tip at a temperature that self-cleans without running so hot that it causes pre-ignition. Both the 2GR-FKS and A25A-FXS call for the same heat range family used in FK20/ILKAR7 plugs.
• Electrode metal: These engines are designed for laser iridium fine-wire plugs. Iridium offers superior durability and a consistent spark kernel over very long intervals. Platinum is acceptable in some older designs but will not meet Toyota’s specified service interval here. Copper plugs provide great conductivity but wear quickly—unsuitable for modern coil-on-plug ignition and long intervals.
• OE design features: The correct plug has the proper reach, seat style, projected tip, and resistor value to play nicely with Toyota’s ignition and combustion chamber design. Substituting “almost right” can trigger misfires, rough idle, or reduced MPG.

How to gap a spark plug

• Check first: New iridium plugs arrive pre-gapped; do not assume they’re correct. Measure with a wire or coin-style gap gauge.
• Target: 0.043 in (1.1 mm). A small variance is okay; excessive bending can crack the fine-wire or fracture the precious-metal pad.
• Adjust gently: If needed, bend only the ground strap—never pry on the iridium center electrode. Use a dedicated gapping tool and make micro-adjustments.
• Re-check: Verify after any tweak. Apply a light touch; many pros will replace rather than aggressively re-gap an iridium plug.

Replacement procedure tips (2022 Highlander)

Both engines use coil-on-plug (COP) ignition—no distributor.

General prep

• Work on a cold engine to avoid thread damage in the aluminum cylinder heads.
• Blow out plug wells with compressed air before removing plugs to keep debris out of the cylinders.

3.5L V6 (2GR-FKS)

• Access: Front bank is straightforward under the engine cover. The rear bank sits near the cowl; remove the plastic cowl trim for more working room, and use wobble extensions. Some techs also remove the wiper tray for best access.
• COP removal: Unclip the harness connectors carefully (brittle with age/heat), remove the 10 mm hold-down bolts, and pull coils straight up.
• Plug service: Thread new plugs by hand with a 5/8 in plug socket and extension; torque to 13 lb-ft (18 Nm). If using a torque wrench is not possible, seat the gasketed plug and add roughly 1/2 turn on a new crush washer (less if reinstalled).

2.5L I4 Hybrid (A25A-FXS)

• Access: Remove the engine cover. Coils and plugs are along the top of the head and are generally easy to reach.
• COP removal and install: Same as above—10 mm bolts, straight-pull removal, hand-thread new plugs, and torque to 13 lb-ft (18 Nm).

Anti-seize and dielectric grease

• Anti-seize: Not recommended on modern plated plugs from NGK/Denso; it alters torque and can cause over-tightening. Dry, clean threads are best. If you must use it, reduce torque by ~20–30%—but the OE guidance is to avoid it.
• Dielectric grease: A small dab inside each coil boot lip helps prevent moisture intrusion and future stuck boots. Do not slather the porcelain.

Final checks

• Reconnect all coils and harnesses before starting. Clear any misfire codes and verify smooth idle.

Known issues

• The 2022 Highlander’s 2GR-FKS V6 and A25A-FXS hybrid engines are not associated with the Ford 3-valve “two-piece” plug breakage or GM ion-sensing coil quirks. Plug removal is generally trouble-free when done cold with proper torque on install.
• Most misfires after service trace to torn coil boots, unseated coil connectors, or over-gapped plugs. Inspect boots and replace any that are oil-soaked or cracked.

Need plugs replaced? Find a shop on Repairius.