P0171System Too Lean (Bank 1)
Voici ce que signifie le code défaut P0171, pourquoi il apparaît et que faire à son sujet.
Système: Fuel & air metering
Généralement sans danger sur de courtes distances, mais faites-le contrôler rapidement.
Ce que signifie P0171
The engine computer detected that the air-fuel mixture on bank 1 is too lean, meaning there is too much air or not enough fuel. The computer added extra fuel to compensate but reached its limit. A lean mixture is commonly caused by unmetered air entering the engine or by weak fuel delivery.
Symptômes courants
- Check engine light
- Rough or unstable idle
- Hesitation or stumble on acceleration
- Loss of power
- Possible engine surging
Causes courantes
Classées de la plus courante à la moins courante.
- 1Vacuum or intake air leak (most common)
- 2Dirty or faulty mass air flow (MAF) sensor
- 3Weak fuel pump or clogged fuel filter (low fuel pressure)
- 4Dirty or clogged fuel injectors
- 5Failing oxygen sensor
- 6Leaking PCV system or intake gasket
Que faire
Have the car checked for vacuum and intake leaks first, since unmetered air is the most frequent cause, and have the MAF sensor inspected or cleaned. If no leaks are found, a professional should test fuel pressure and injector delivery; a persistent lean condition can cause misfires and engine damage over time, so fix it soon.
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Questions fréquentes
Que signifie le code P0171 ?
The engine computer detected that the air-fuel mixture on bank 1 is too lean, meaning there is too much air or not enough fuel. The computer added extra fuel to compensate but reached its limit. A lean mixture is commonly caused by unmetered air entering the engine or by weak fuel delivery.
Quelles sont les causes du code P0171 ?
Les causes les plus courantes sont : Vacuum or intake air leak (most common), Dirty or faulty mass air flow (MAF) sensor, Weak fuel pump or clogged fuel filter (low fuel pressure), Dirty or clogged fuel injectors, Failing oxygen sensor, Leaking PCV system or intake gasket.
Peut-on rouler sans danger avec le code P0171 ?
Généralement sans danger sur de courtes distances, mais faites-le contrôler rapidement.
Comment corriger le code P0171 ?
Have the car checked for vacuum and intake leaks first, since unmetered air is the most frequent cause, and have the MAF sensor inspected or cleaned. If no leaks are found, a professional should test fuel pressure and injector delivery; a persistent lean condition can cause misfires and engine damage over time, so fix it soon.
Ce sont des informations générales pour vous aider à comprendre le code P0171, 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.