P0421
Warm Up Catalyst Efficiency Below Threshold Bank 1
2003-2003 Aston Martin DB7 3.2L I6 Supercharged 🇷🇺
Moderate SeverityPowertrain
Description
The Bank 1 warm-up catalytic converter is not efficient during the warm-up period.
Symptoms
- Check Engine Light
- Failed emissions test
Common Causes
- Worn catalyst
- Engine running rich during warm-up
- O2 sensor issue
- Exhaust leak
Diagnostic Steps
- Monitor catalyst temps during warm-up
- Compare O2 sensor signals
- Check for exhaust leaks
Repair Notes
Replace warm-up catalyst if confirmed failed.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P0421 on Other Vehicles
Aston Martin DB11
2016-2016 4.0L V8 Twin Turbo
Aston Martin DB11
2016-2016 5.2L V12 Twin Turbo
Aston Martin DB11
2017-2017 4.0L V8 Twin Turbo
Aston Martin DB11
2017-2017 5.2L V12 Twin Turbo
Aston Martin DB11
2018-2018 4.0L V8 Twin Turbo
Aston Martin DB11
2018-2018 5.2L V12 Twin Turbo
Aston Martin DB11
2019-2019 4.0L V8 Twin Turbo
Aston Martin DB11
2019-2019 5.2L V12 Twin Turbo
Common Questions
What does code P0421 mean on a 2003-2003 Aston Martin DB7?
P0421 stands for "Warm Up Catalyst Efficiency Below Threshold Bank 1". The Bank 1 warm-up catalytic converter is not efficient during the warm-up period.
What are the symptoms of P0421 on a Aston Martin DB7?
Common symptoms of P0421 include: Check Engine Light, Failed emissions test.
What causes P0421 on a 2003-2003 Aston Martin DB7?
Common causes of P0421 include: Worn catalyst, Engine running rich during warm-up, O2 sensor issue, Exhaust leak.