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OBDII Code List
P0420 1997 HONDA CIVIC

P0420 1997 HONDA CIVIC - 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
  • Bank 1 sensor 2 oxygen sensor (Secondary HO2S)
  • 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)
What does this mean?
OBDII Code P0420 1997 Honda Civic - Catalyst System Efficiency Below Threshold Bank 1 -

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Posted and Edit by 04-18-2017