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P0201 on Toyota 4Runner

Injector Circuit Malfunction - Cylinder 1

Factory diagnostic protocol and troubleshooting wire for fault code P0201 specifically for the Toyota 4Runner (2020–2026, 4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl).

Verified OEM Telemetry & Field Repair Tree
Toyota 4Runner2020–2026
Toyota 4Runner
SUV4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
4Runner SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Not Recommended
Critical urgency level
Est. Repair Cost
$150 - $550 (DIY: $40 - $180)
Parts & Labor DIY
Check P0201 On Another Toyota Model:
Diagnose P0201 on Specific 4Runner Model Year:

1. Symptoms of P0201 on Toyota 4Runner

When the Engine Control Module (ECM/PCM) on your Toyota 4Runner (4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl) logs fault code P0201, drivers commonly observe:

Flashing or steady Check Engine Light on Toyota 4Runner (4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl)
Severe engine shaking, shuddering, and rough running on Toyota 4Runner (4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl)
Dramatic loss of acceleration power on Toyota 4Runner (4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl)
Accompanying code P0301 (Cylinder 1 Misfire) on Toyota 4Runner (4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl)
Toyota 4Runner OBD-II Port Location
The 16-pin diagnostic connector is located Lower dashboard near parking brake mechanism. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Toyota 4Runner

Historical warranty claims and technical repair bulletins for Toyota 4Runner point to the following failure distribution:

55%
Failed, open, or shorted fuel injector solenoid on Cylinder 1 (Toyota OEM Part)
25%
Damaged or chewed wiring harness to Cylinder 1 injector (Toyota OEM Part)
12%
Loose or corroded injector connector clip (Toyota OEM Part)
8%
Faulty injector driver circuit in the ECM / PCM (Toyota OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Toyota 4Runner.

3. Step-by-Step DIY Repair Guide for Toyota 4Runner

01
Check Cylinder 1 Injector Connector

Locate Cylinder 1 fuel injector. Ensure connector is securely clicked in and wires are not frayed. on the Toyota 4Runner equipped with 4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl.

Required Tool: Flashlight
02
Test Injector Coil Resistance

Unplug connector and measure resistance across the two injector pins. Normal is 11–16 ohms for high-impedance injectors. If open (OL) or shorted (0 ohms), replace injector. on the Toyota 4Runner equipped with 4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl.

Required Tool: Digital Multimeter
03
Test Pulse Signal with Noid Light

Plug a noid light into the harness connector and crank engine. Rapid flashing confirms PCM driver is pulsing the circuit. on the Toyota 4Runner equipped with 4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl.

Required Tool: Noid Light Kit
04
Replace Cylinder 1 Fuel Injector

Relieve fuel rail pressure, unbolt fuel rail mounting bolts, gently pull rail up, remove retaining clip, and replace Cylinder 1 injector with new OEM unit with lubricated O-rings. on the Toyota 4Runner equipped with 4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl.

Required Tool: Fuel Line Tool, Socket Set, Clean Engine Oil for O-rings
05
Clear Trouble Codes & Test Drive

Turn key to ON to prime fuel system, check for fuel rail leaks, start engine, clear DTCs, and verify smooth idle. on the Toyota 4Runner equipped with 4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl.

Required Tool: OBD-II Scanner
Recommended Parts & Testing Tools

Equipment for Diagnosing Toyota 4Runner (P0201)

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Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

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Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

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Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

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Other Common Fault Codes on Toyota 4Runner

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Toyota 4Runner:

4. Toyota 4Runner P0201 FAQs

What causes code P0201 to trigger on a Toyota 4Runner?

On the Toyota 4Runner (4.0L V6 (1GR-FE) / 2.4L i-FORCE Turbo 4-Cyl), P0201 is most frequently caused by Failed, open, or shorted fuel injector solenoid on Cylinder 1 or Damaged or chewed wiring harness to Cylinder 1 injector.

Where is the OBD-II port located on my Toyota 4Runner?

On the Toyota 4Runner, the 16-pin DLC diagnostic connector is located Lower dashboard near parking brake mechanism. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Toyota 4Runner with code P0201?

No. Dead injector on Cylinder 1 causes immediate dead misfire, severe shaking, and unburned air/fuel delivery imbalance. Given that P0201 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.