P0420Catalyst System Efficiency Below Threshold (Bank 1)
Voici ce que signifie le code défaut P0420, pourquoi il apparaît et que faire à son sujet.
Système: Catalyst / emissions
Généralement sans danger sur de courtes distances, mais faites-le contrôler rapidement.
Ce que signifie P0420
The computer compares the oxygen sensors before and after the catalytic converter on bank 1 to judge how well it is cleaning the exhaust. This code means the converter on bank 1 is no longer working efficiently enough. Most often the catalytic converter itself is worn out, but a faulty sensor or an exhaust leak can also trigger it.
Symptômes courants
- Check engine light on
- Often no change in how the car drives
- Possible mild loss of power or rotten-egg (sulfur) smell
- Reduced fuel economy in some cases
- Will fail an emissions test
Causes courantes
Classées de la plus courante à la moins courante.
- 1Worn-out or failing catalytic converter (bank 1)
- 2Failed or lazy downstream O2 sensor
- 3Exhaust leak before or near the converter or sensors
- 4Engine running rich/lean or misfiring, damaging the converter
- 5Aftermarket or low-quality converter that doesn't meet spec
- 6Oil or coolant contamination of the converter
Que faire
You can usually keep driving short distances; this is an emissions code, not an immediate safety risk. However, have it diagnosed before replacing the costly converter, because an exhaust leak, a bad sensor, or an unresolved misfire can cause it. Fixing any upstream problem first prevents ruining a new converter.
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Questions fréquentes
Que signifie le code P0420 ?
The computer compares the oxygen sensors before and after the catalytic converter on bank 1 to judge how well it is cleaning the exhaust. This code means the converter on bank 1 is no longer working efficiently enough. Most often the catalytic converter itself is worn out, but a faulty sensor or an exhaust leak can also trigger it.
Quelles sont les causes du code P0420 ?
Les causes les plus courantes sont : Worn-out or failing catalytic converter (bank 1), Failed or lazy downstream O2 sensor, Exhaust leak before or near the converter or sensors, Engine running rich/lean or misfiring, damaging the converter, Aftermarket or low-quality converter that doesn't meet spec, Oil or coolant contamination of the converter.
Peut-on rouler sans danger avec le code P0420 ?
Généralement sans danger sur de courtes distances, mais faites-le contrôler rapidement.
Comment corriger le code P0420 ?
You can usually keep driving short distances; this is an emissions code, not an immediate safety risk. However, have it diagnosed before replacing the costly converter, because an exhaust leak, a bad sensor, or an unresolved misfire can cause it. Fixing any upstream problem first prevents ruining a new converter.
Ce sont des informations générales pour vous aider à comprendre le code P0420, et non un substitut au diagnostic d’un mécanicien qualifié. Confirmez toujours la cause avant de remplacer des pièces.
Les définitions des codes suivent la liste OBD-II normalisée (SAE J2012). CarVinVin est indépendant et n’est affilié à aucun constructeur.