Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the sensor in your car that checks how much pollution is coming out of the exhaust is not working quickly enough.
The NOx sensor measures the levels of nitrogen oxides in the exhaust gases. This code indicates that the sensor's response time from low to high readings is slower than expected.
The P22FC code is triggered when the Engine Control Module (ECM) detects that the NOx sensor located on Bank 1, Sensor 2, is not responding as quickly as it should when transitioning from low to high NOx levels. This can affect the vehicle's emissions control system.
• Check Engine Light is on
• Decreased fuel efficiency
• Poor engine performance
• Faulty NOx sensor
• Wiring issues or poor connections
• Exhaust leaks near the sensor
NOx: Nitrogen Oxides, a group of gases that are major pollutants.
ECM: Engine Control Module, the computer that controls the engine.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the NOx sensor.
• Check for exhaust leaks around the sensor.
• Replace the faulty NOx sensor.
• Repair or replace damaged wiring or connectors.
• Fix any exhaust leaks.
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $400
Moderate
• Volkswagen Passat
• Audi A4
• BMW 3 Series
• Regularly check and maintain exhaust system.
• Ensure timely replacement of sensors.
• Avoid using low-quality fuel.
Sensor Issue
• Have the vehicle inspected by a professional.
• Do not ignore the Check Engine Light.
• Monitor fuel efficiency for any changes.
Check with your vehicle manufacturer for specific warranty coverage on emissions-related components.
This code has become more common with the increased use of NOx sensors in modern vehicles to meet emissions standards.
Moderate – It affects emissions and fuel efficiency, so it should be addressed soon.
Driving with a faulty NOx sensor may lead to increased emissions, which can be illegal in some areas.
• Engine at operating temperature
• Vehicle in closed-loop mode
The NOx sensor is typically located in the exhaust system, downstream of the catalytic converter on Bank 1.
Q: What does a NOx sensor do?
A: A NOx sensor measures the levels of nitrogen oxides in the vehicle's exhaust to help control emissions.
Q: Can I drive with a P22FC code?
A: While the car may still run, it's not advisable to drive for long periods with this code as it affects emissions and fuel efficiency.
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Universal · Digital multimeter
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Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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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.