P0430high severityPowertrain
Catalyst System Efficiency Below Threshold Bank 2
on 2000 Chevrolet Impala 3.4L V6 · FWD
What this code means
The Bank 2 catalytic converter is not performing efficiently. Same as P0420 but for Bank 2.
Symptoms
- Check Engine Light
- Failed emissions test
- Possible sulfur smell
Common causes
- Worn catalytic converter
- Exhaust leak near downstream O2
- Faulty O2 sensor Bank 2
- Misfire damage to catalyst
- Oil contamination
Diagnostic steps
- Compare upstream/downstream O2 waveforms Bank 2
- Check for exhaust leaks
- Test downstream O2 sensor Bank 2
- Check for misfire codes
- Inspect for oil consumption
Repair notes
Same approach as P0420 but for Bank 2. Replace catalyst if confirmed failed.
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0006
Fuel Shutoff Valve A Control Circuit Low
P0007
Fuel Shutoff Valve A Control Circuit High
P0008
Engine Position System Performance - Bank 1
P0009
Engine Position System Performance - Bank 2
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1