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 car's computer is having trouble getting the right power to a sensor that checks for pollution in the exhaust. It's like if your TV remote didn't have enough battery power to work properly.
The P220A code indicates an issue with the supply voltage to the NOx sensor located in Bank 1, Sensor 1. This sensor is responsible for measuring nitrogen oxide levels in the exhaust gases.
The NOx sensor is part of the vehicle's emissions control system. It monitors the concentration of nitrogen oxides in the exhaust. The sensor requires a specific voltage to operate correctly. If the sensor doesn't receive the correct voltage, it can't provide accurate readings, leading to emissions control issues.
• Check Engine Light is on
• Decreased fuel efficiency
• Increased emissions
• Faulty NOx sensor
• Wiring issues or poor electrical connections
• Faulty power supply to the sensor
NOx: Nitrogen Oxides, which are pollutants produced during combustion.
Bank 1: The side of the engine with cylinder 1, typically the side with the number one cylinder in a V-type engine.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Check the voltage supply to the NOx sensor.
• Replace the NOx sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Ensure the power supply to the sensor is within specifications.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $500
Moderate
• Volkswagen Jetta
• Audi A4
• BMW 3 Series
• Regular maintenance checks on the exhaust system.
• Ensure proper electrical connections.
• Use quality fuel to reduce emissions.
Sensor Issue
• Have the vehicle inspected by a professional.
• Avoid prolonged driving with this code active to prevent further damage.
• Consider regular diagnostics to catch issues early.
Check if the vehicle's emissions system is covered under warranty, as many manufacturers provide extended coverage for emissions-related components.
This code has become more common with the increased use of NOx sensors in modern vehicles to meet stricter emissions standards.
Moderate – While not immediately critical, addressing this issue promptly can prevent further emissions system damage and ensure compliance with emissions standards.
Driving with a malfunctioning emissions system can lead to increased pollution and may result in failing emissions tests required by law.
• Engine running at operating temperature
• Vehicle in closed-loop operation
The NOx sensor is typically located in the exhaust system, upstream of the catalytic converter on Bank 1.
Q: What is a NOx sensor?
A: A NOx sensor measures the levels of nitrogen oxides in the vehicle's exhaust gases to help control emissions.
Q: Can I drive with a P220A code?
A: While you can drive with this code, it's best to address it soon to avoid increased emissions and potential damage to the emissions system.
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Useful when diagnosis points toward damaged wiring, corroded terminals, or connector 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.