HC Adsorption Catalyst Efficiency Below Threshold - Bank 2
The P2424 code means the vehicle's onboard diagnostic system has detected: HC Adsorption Catalyst Efficiency Below Threshold - Bank 2. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- hard
- Estimated cost
- $200 - $1500 (parts and labor)
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What Are the Symptoms of P2424?
- Check Engine Light illuminated
- Failed emissions test for hydrocarbons
- Mild fuel odor from exhaust
- Reduced catalytic converter efficiency on bank 2
- No significant drivability symptoms
What Causes P2424? (Most Likely First)
- Degraded HC adsorption catalyst on bank 2 Very High
- Rich fuel mixture contaminating bank 2 catalyst High
- Exhaust leak on bank 2 before the catalyst Moderate
- Oil consumption fouling the catalyst Moderate
Can I Still Drive with P2424?
Short distances only. P2424 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
Can I drive with code P2424?
Short distances are fine. The vehicle will have elevated hydrocarbon emissions but is generally safe to drive.
What causes P2424?
A degraded catalyst on bank 2 is most common. Address any rich-running conditions first as they accelerate catalyst deterioration.
Is P2424 expensive to fix?
Costs range from $200 to $1500. European vehicle catalytic converters are expensive. Fix root causes like rich running or oil burning first.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose P2424?
-
Compare bank 1 and bank 2 catalyst efficiency readings
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Check for rich-running conditions on bank 2 using fuel trim data
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Inspect exhaust manifold and pipes on bank 2 for leaks
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Check for oil consumption that could foul the catalyst
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Evaluate O2 sensor readings upstream and downstream of the bank 2 catalyst
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
- Cross-checked against the SAE J2012:2002 DTC table (2026-08-27)archived scan of the SAE standard — readable copy, not SAE’s current edition
Which Vehicles Commonly Get P2424?
- 2012-2020 BMW 5 Series
- 2013-2021 Audi A6
- 2014-2022 Mercedes-Benz E-Class
- 2011-2019 Volkswagen Touareg
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