Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car has a sensor that checks how much bad gas (NOx) is coming out of the engine. This sensor is not working fast enough to catch changes in the gas levels.
The NOx sensor is responsible for measuring nitrogen oxide levels in the exhaust. This code indicates that the sensor is slow in detecting changes from high to low NOx levels.
The P22FD code is triggered when the NOx sensor located in Bank 1, Sensor 2, does not respond quickly enough to changes in exhaust NOx levels. This can affect the vehicle's emission control system, leading to higher emissions.
• Check Engine Light is on
• Poor fuel economy
• Failed emissions test
• Faulty NOx sensor
• Wiring issues or poor connections
• Exhaust leaks
NOx: Nitrogen Oxides, harmful pollutants produced during combustion.
Bank 1: The side of the engine with cylinder 1.
• Use an OBD-II scanner to confirm the code.
• Inspect the NOx sensor and wiring for damage.
• Check for exhaust leaks.
• Replace the faulty NOx sensor.
• Repair any damaged wiring or connections.
• Fix any exhaust leaks.
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $600
Moderate
• Volkswagen Jetta
• Audi A4
• BMW 3 Series
• Regularly inspect and maintain the exhaust system.
• Ensure timely replacement of sensors.
• Use quality fuel to reduce sensor contamination.
Sensor Issue
• Get the sensor checked as soon as possible to avoid further issues.
• Avoid driving aggressively until the issue is resolved.
Sensor issues may be covered under the vehicle's emissions warranty.
This code has become more common with the increased use of NOx sensors in modern vehicles to meet stricter emissions standards.
Moderate – While the vehicle can still be driven, it should be addressed soon to avoid increased emissions and potential damage.
Driving with a malfunctioning NOx sensor can lead to higher emissions, which may not comply with legal standards.
• Engine at operating temperature
• Vehicle in closed-loop operation
The NOx sensor is located in the exhaust system, downstream of the catalytic converter in Bank 1.
Q: Can I drive with a P22FD code?
A: Yes, but it's best to get it fixed soon to avoid increased emissions and potential fines.
Q: What happens if I ignore this code?
A: Ignoring it can lead to poor fuel economy, failed emissions tests, and potential engine damage.
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