P01F1
O2 Sensor Circuit Bank 1 Sensor 4
Generic electrical fault on the bank 1, sensor 4 oxygen sensor (fourth sensor downstream — used on systems with multiple cat stages or NOx-trap diagnosis).
Generic electrical fault on the bank 1, sensor 4 oxygen sensor (fourth sensor downstream — used on systems with multiple cat stages or NOx-trap diagnosis).
Common causes
- high
Sensor failed
One of the most commonly reported causes for this code — check this first.
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 P01F1 mean?
P01F1 means "O2 Sensor Circuit 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 P01F1?
sensor failed — 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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