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 thinks a part of the exhaust system, called the NOx adsorber, isn't working well enough on one side of the engine.
The NOx adsorber is a component in the exhaust system that helps reduce harmful nitrogen oxide emissions. When its efficiency falls below a certain threshold, the engine control module (ECM) triggers the P2001 code.
The P2001 code is set when the ECM detects that the NOx adsorber on Bank 2 of the engine is not reducing nitrogen oxide emissions effectively. This can be due to a malfunctioning adsorber, a problem with the sensors, or issues with the exhaust system.
• Check Engine Light is on
• Increased emissions
• Possible reduction in fuel efficiency
• Faulty NOx adsorber
• Exhaust leaks
• Defective oxygen or NOx sensors
NOx: Nitrogen oxides, harmful pollutants produced by vehicles.
Adsorber: A device that captures and holds substances, in this case, NOx gases.
• Use an OBD-II scanner to confirm the code.
• Inspect the NOx adsorber and associated sensors.
• Check for exhaust leaks or damage.
• Replace the faulty NOx adsorber.
• Repair any exhaust leaks.
• Replace defective sensors.
• OBD-II scanner
• Wrench set
• Multimeter
$500 - $1500
Moderate
• Volkswagen Passat
• Audi A4
• BMW 3 Series
• Regular maintenance of the exhaust system
• Use high-quality fuel
• Timely replacement of sensors
Emission Control
• Do not ignore the Check Engine Light.
• Seek professional diagnosis if unsure.
• Regularly service the vehicle to prevent emission issues.
Check with the vehicle manufacturer for emission-related warranty coverage.
This code has become more common with the increased use of NOx adsorbers in modern vehicles to meet emission standards.
Moderate – While the vehicle may still drive normally, increased emissions can lead to environmental harm and potential legal issues.
Driving with this code may cause the vehicle to fail emissions tests, which could be illegal in some areas.
• Engine at operating temperature
• Vehicle in closed-loop operation
The NOx adsorber is located in the exhaust system, typically near the catalytic converter on Bank 2.
Q: Can I drive with a P2001 code?
A: Yes, but it's not recommended due to increased emissions and potential legal issues.
Q: How do I know which bank is Bank 2?
A: Bank 2 is the side of the engine opposite to Bank 1, which usually contains cylinder 1.
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Fitment Required · Vehicle-fitment part
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