For Shop Owners

P0420 - Catalyst System Efficiency Below Threshold Bank 1

Repair Importance Level: 2/3
Repair Difficulty Level: 2/3 What does this mean?

Possible causes

  • Three way catalyst converter Bank 1
  • Exhaust tube
  • Intake air leaks
  • Fuel injectors may be faulty
  • Fuel injector leaks
  • Spark plugs may be faulty
  • Improper ignition timing
  • Engine Control Module (ECM)
  • Dirty air filter
What does this mean?
OBDII Code P0420 - Catalyst System Efficiency Below Threshold Bank 1 - kvjournal.ru

P0420 Information for specific makes

  • P0420 ACURA Catalyst System Efficiency Below Threshold Bank 1
  • P0420 AUDI Catalyst System Efficiency Below Threshold Bank 1
  • P0420 BMW Catalytic Converter Conversion
  • P0420 BUICK Catalyst System Low Efficiency Bank 1
  • P0420 CADILLAC Catalyst System Low Efficiency Bank 1
  • P0420 CHEVROLET Catalyst System Low Efficiency Bank 1
  • P0420 CHRYSLER Catalyst System Efficiency Bank 1
  • P0420 DODGE Catalyst System Efficiency Bank 1
  • P0420 FORD Catalyst System Efficiency Below Threshold Bank 1
  • P0420 GMC Catalyst System Low Efficiency Bank 1
  • P0420 HONDA Catalyst System Efficiency Below Threshold Bank 1
  • P0420 HYUNDAI Warm Up Catalyst Efficiency Below Threshold Bank 1
  • P0420 INFINITI Catalyst System Efficiency Below Threshold Bank 1
  • P0420 ISUZU Catalyst System Low Efficiency Bank 1
  • P0420 JAGUAR Catalyst System Efficiency Below Threshold Bank 1
  • P0420 JEEP Catalyst System Efficiency Bank 1
  • P0420 KIA Warm Up Catalyst Efficiency Below Threshold Bank 1
  • P0420 LEXUS Catalyst System Efficiency Below Threshold Bank 1
  • P0420 MAZDA Catalyst System Efficiency Below Threshold Bank 1
  • P0420 MERCEDES-BENZ Catalyst System Efficiency Below Threshold Bank 1
  • P0420 MINI Catalytic Converter Conversion
  • P0420 MITSUBISHI Catalyst System Efficiency Below Threshold Bank 1
  • P0420 NISSAN Catalyst System Efficiency Below Threshold Bank 1
  • P0420 PONTIAC Catalyst System Low Efficiency Bank 1
  • P0420 SATURN Catalyst System Low Efficiency Bank 1
  • P0420 SCION Catalyst System Efficiency Below Threshold Bank 1
  • P0420 SUBARU Catalyst System Efficiency Below Threshold
  • P0420 TOYOTA Catalyst System Efficiency Below Threshold Bank 1
  • P0420 VOLKSWAGEN Catalyst System Efficiency Below Threshold Bank 1
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    Posted and Edit by kvjournal.ru 05-27-2017