Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car has a sensor that checks how well the engine is burning fuel. This code means that one of those sensors isn't working right.
The O2 sensor measures the amount of oxygen in the exhaust gases. This code indicates a problem with the circuit of the sensor located on Bank 1, Sensor 4.
The P01F1 code is triggered when the Powertrain Control Module (PCM) detects a malfunction in the oxygen sensor circuit for Bank 1, Sensor 4. This sensor is responsible for monitoring the oxygen levels in the exhaust gases after they have passed through the catalytic converter.
• Check Engine Light is on
• Poor fuel economy
• Engine runs rough
• Faulty O2 sensor
• Wiring issues such as shorts or opens in the circuit
• Poor electrical connection
O2 Sensor: A device that measures the oxygen level in the exhaust gases.
PCM: Powertrain Control Module, the car's computer that manages engine and transmission functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the O2 sensor.
• Test the O2 sensor with a multimeter.
• Replace the faulty O2 sensor.
• Repair or replace damaged wiring or connectors.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Socket set
$150 - $300
Moderate
• Toyota Camry
• Honda Accord
• Ford F-150
• Regularly inspect and maintain the exhaust system.
• Ensure timely replacement of oxygen sensors.
• Keep electrical connections clean and secure.
Sensor Issue
• Get the issue diagnosed and repaired promptly to avoid further engine problems.
• Consider using a fuel additive to clean the fuel system.
Oxygen sensors may be covered under the emissions warranty, typically up to 80,000 miles.
Oxygen sensor issues are common in vehicles with high mileage, especially if maintenance is neglected.
Moderate – While the car may still run, ignoring this issue can lead to decreased fuel efficiency and potential damage to the catalytic converter.
Driving with a malfunctioning O2 sensor can lead to increased emissions, which may not comply with local environmental regulations.
• Engine at operating temperature
• Vehicle in closed-loop operation
The O2 sensor for Bank 1, Sensor 4 is typically located downstream of the catalytic converter on the exhaust system of the engine's first bank.
Q: Can I drive with a P01F1 code?
A: Yes, but it's not recommended for long periods as it can lead to poor fuel economy and potential damage to the catalytic converter.
Q: How often should O2 sensors be replaced?
A: O2 sensors typically last between 60,000 to 90,000 miles, but it's best to follow the manufacturer's recommendations.
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Fitment Required · Vehicle-fitment part
Relevant when the code or supporting diagnostics point toward upstream or downstream oxygen-sensor faults.
This code family often involves upstream or downstream oxygen-sensor diagnosis.
Verify exact sensor position and vehicle fitment before buying.
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Fitment Required · Vehicle-fitment part
Relevant when catalyst-efficiency or emissions faults persist after proper diagnosis.
Catalyst-efficiency faults sometimes point toward converter problems after proper testing.
Catalytic converters are highly vehicle-specific and should not be purchased by code alone.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.