AI Diesel Tech
P0430OBD-IIEMISSIONS

Catalyst System Efficiency Below Threshold (Bank 2)

Common Symptoms

  • Check Engine Light illuminated
  • Slight decrease in fuel economy
  • Rotten egg smell from exhaust
  • No noticeable driveability issues in most cases
  • Failed emissions test

Most Likely Root Causes

  • Catalytic converter failure or degradation on Bank 2
  • Faulty or contaminated downstream oxygen sensor on Bank 2
  • Engine oil or coolant contamination of the catalyst
  • Exhaust leaks upstream of the catalyst or between oxygen sensors
  • Rich or lean fuel mixture damaging the catalyst over time

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Component Location

Bank 2 catalytic converter is located in the exhaust system on the side opposite cylinder one, downstream of the exhaust manifold.

Manufacturer Notes

Some manufacturers require specific drive cycle conditions to be met before catalyst efficiency monitoring becomes active after repairs.

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