LEMON Manuals: Even more car manuals for everyone
Home >> Pontiac >> 2009 >> Vibe Base, 2.4 0, AWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 9 (Engine Control System & Fuel System - 1.8L (Lay) - DTC P0010 To DTC P0420) >> DTC P0420 >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.
  1. Verify the following conditions do not exist with the catalytic converter:
    • Dents
    • A severe discoloration caused by excessive temperatures
    • Road damage
    • An internal rattle caused by damaged catalyst substrate
    • Exhaust flow restrictions - Refer to Restricted Exhaust .
    • If a condition is found, replace the catalytic converter.
  2. Verify the following conditions do not exist with the exhaust system:
    • Leaks - Refer to Exhaust Leakage .
    • Physical damage
    • Loose or missing hardware
    • Properly torqued HO2S
    • If a condition is found, repair the exhaust system.
  3. Verify the following conditions do not exist with the HO2S 2:
    • A grounded wiring harness
    • Damage
    • If a condition is found, replace the HO2S 2.
  4. Engine running at normal operating temperatures, increase the engine speed to 2,500-3,000 RPM for 3 minutes. Engine at idle, observe the scan tool HO2S 2 parameter for 1 minute. The HO2S 2 voltage should not be actively switching above and below 450 mV.
    • If the voltage is actively switching, replace the TWC converter.