6th Gen 4Runner: Check engine light on, with or without a code

Checks, in order

1. Gas cap and fueling
   Tighten the cap until it clicks. An evap code may clear by itself after several drive cycles.
   easy $ · under about $50
2. Read the codes
   Use a basic OBD2 reader and write down the exact code and any freeze-frame data. Do not clear it before the dealer has seen it unless you have recorded it.
   easy $ · under about $50
3. Is it flashing
   A flashing light means active misfire. Reduce power and get it checked soon to protect the catalytic converter.
   easy $ · under about $50
4. Note any drivability symptoms
   Rough running, power loss or boost issues alongside the light helps the dealer find the cause. Tell them about recent fuel, towing or modifications.
   easy $ · under about $50
5. Dealer diagnosis
   On a truck under warranty, let the dealer diagnose it. They can check for software updates and have access to Toyota's diagnostics.
   hard $$$ · shop-level job, $500+

Applies to: 6th generation 4Runner, 2025 and newer, with the 2.4L turbocharged i-FORCE and the i-FORCE MAX hybrid, both with the 8-speed automatic. This is a new platform with little long-term history, so most entries are general symptoms; when the truck is under warranty, the dealer is the right first stop.

Tools and parts for these checks

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Other engine problems on the 6th Gen 4Runner

• Fluid leak or drip under the truck
• Poor fuel economy or loss of power, limp mode

More 6th Gen 4Runner problems

• Something is wrong on a new 4Runner: warranty, recalls and where to start (Body & Electrical)
• Digital gauge cluster blank, missing speedometer, or warning lights not showing at startup (Body & Electrical)
• Clunk or abrupt shift, especially 1st to 2nd, or hesitation pulling away (Transmission)
• Front brakes squealing or chirping on a new truck (Brakes)
• Hybrid won't go to READY, or dead 12 V battery in the i-FORCE MAX (Hybrid System)
• Won't start or crank on the 2.4L turbo (non-hybrid) (Starting & Charging)

All 14 6th Gen 4Runner symptoms in the interactive troubleshooter →

General guidance from owner experience. Confirm torque specs, fluid capacities and procedures in the factory service manual. Brakes, steering and anything structural: if in doubt, have a qualified shop inspect it before driving.