What Does P2001 Mean?
The NOx adsorber catalyst on Bank 2 is not reducing nitrogen oxide emissions efficiently enough to meet standards. This is the same condition as P2000 but for the opposite cylinder bank in V-configuration engines.
Common Causes
40%
Degraded or contaminated NOx adsorber catalyst due to age or fuel contamination
25%
Faulty NOx sensor on Bank 2 providing incorrect efficiency readings
15%
Exhaust leaks on Bank 2 affecting sensor accuracy
12%
Insufficient regeneration cycles or inadequate desulfation
8%
Bank 2 specific fuel delivery issues affecting catalyst efficiency
Diagnostic Steps
1
Step 1: Monitor NOx sensor data for Bank 2 upstream and downstream to verify efficiency calculation
2
Step 2: Inspect Bank 2 exhaust system for leaks, particularly around sensors and catalyst
3
Step 3: Compare Bank 1 and Bank 2 NOx readings to identify bank-specific issues
4
Step 4: Check Bank 2 fuel trims and air/fuel ratios for proper engine balance
5
Step 5: Perform catalyst regeneration procedure and monitor Bank 2 NOx reduction effectiveness
Estimated Repair Cost
$300 - $3,500
Parts + labor, varies by vehicle and location
The NOx adsorber catalyst on Bank 2 is not reducing nitrogen oxide emissions efficiently enough to meet standards. This is the same condition as P2000 but for the opposite cylinder bank in V-configuration engines.
The most common cause of P2001 (NOx Adsorber Efficiency Below Threshold Bank 2) is: Degraded or contaminated NOx adsorber catalyst due to age or fuel contamination
Typical repair costs for P2001 range from $300 to $3,500, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle is safe to drive but will fail emissions testing and produce higher pollutants. Some vehicles may enter reduced power mode if not addressed.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P2001 to identify the root cause.
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Quick Info
Category
Powertrain
System
Emissions Control System
Difficulty
Type
Generic (SAE)
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