P01F3
O2 Sensor Circuit High Voltage Bank 1 Sensor 4
Bank 1 sensor 4 O2 sensor signal voltage above expected range — short to power or sensor stuck high. A drifted or sluggish lambda sensor lets the mixture run lean or rich without correction — fuel economy and emissions suffer immediately.
Bank 1 sensor 4 O2 sensor signal voltage above expected range — short to power or sensor stuck high. A drifted or sluggish lambda sensor lets the mixture run lean or rich without correction — fuel economy and emissions suffer immediately.
Common causes
- high
Signal wire shorted to battery
One of the most commonly reported causes for this code — check this first.
Typical part cost: $90-440
- low
Connector pins corroded - high contact resistance
Less common, but worth ruling out after the more likely causes.
Typical part cost: $90-440
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P01F3 mean?
P01F3 means "O2 Sensor Circuit High Voltage Bank 1 Sensor 4". It is a generic OBD-II code that points to a fault in the fuel & air metering.
What are the most common causes of P01F3?
signal wire shorted to battery; connector pins corroded - high contact resistance; supply wire pinched against b+ source — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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