OBD O2 Sensor Circuit High Voltage Bank 1 Sensor 4
What it means
P01F3 stands for O2 Sensor Circuit High Voltage Bank 1 Sensor 4. P01F3 is a P code, so the fault sits in the engine, transmission and emissions systems. For P01F3, the second digit places it in fuel and air metering. For P01F3, work through the cause list below, cheapest checks first.
Where it lives
For P01F3, the circuit described runs through the sensor. The description of P01F3 puts it on bank 1.
What to check first
For P01F3, check the bank 1 reading against the other bank before buying parts, since if only one side is out of range that side is the fault.
Check these first
- P01F3: Faulty or contaminated sensor in the fuel/air metering circuit
- P01F3: Damaged or shorted wiring or connector for the affected circuit
- P01F3: Vacuum leak or intake system restriction
- P01F3: Failing fuel pump, injector, or fuel pressure regulator
What to do next
P01F3 is a fault in the fuel and air metering system. The steps below are general, so what actually failed on your vehicle may not be what P01F3 names.
- P01F3: Read freeze frame data and related codes with an OBD-II scanner
- P01F3: Inspect the affected sensor wiring and connector for damage
- P01F3: Compare live sensor readings (fuel trim, airflow, temperatures) to manufacturer specs
- P01F3: Smoke test the intake system if lean or vacuum conditions are suspected
- P01F3: Replace the failed component after confirming it with live data
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Updated
Generic SAE J2012 definition. Last updated 2026-08-30.