P2187: System Too Lean at Idle (Bank 1)

P2187 means the engine is running too lean specifically at idle speed on Bank 1. The fuel system is not delivering enough fuel relative to the amount of air entering the engine at low RPM. This is different from P0171, which indicates a lean condition across all operating ranges.

P2187 è un codice diagnostico di guasto relativo a sistema di alimentazione, classificato con gravità moderate. Quando la centralina (ECU) del tuo veicolo rileva questa condizione, memorizza P2187 e accende la spia motore.

Se il tuo veicolo ha attivato P2187, potresti notare uno o più di questi sintomi:

• Check engine light illuminated
• Rough or unstable idle
• Engine hunting or surging at idle
• Occasional misfires at idle
• Slight hesitation when pulling away from standstill
• Hissing or whistling noise from engine bay at idle

Ecco le cause più comuni di P2187, ordinate in base alla probabilità che siano la causa del problema:

In genere sì, per brevi tragitti. Short-term driving is acceptable but a lean condition can cause engine overheating and catalyst damage over time. Avoid heavy loads or sustained high-speed driving until diagnosed.

Segui questi passaggi per individuare la causa principale di P2187:

1. With the engine idling, listen carefully for any hissing or whistling sounds around the intake manifold, vacuum hoses, and PCV system. A vacuum leak is the most common cause and often audible.
2. Use a smoke machine to pressurize the intake system and find vacuum leaks. Smoke will escape from any crack, split hose, or faulty gasket. Pay special attention to the intake manifold gasket and brake servo hose.
3. Check the MAF sensor readings at idle using live data. Compare the actual airflow reading to the manufacturer's specification for your engine. A dirty MAF sensor will underreport airflow, causing the ECU to deliver too little fuel.
4. Monitor short-term and long-term fuel trims at idle. Values above +10% confirm the ECU is adding fuel to compensate for a lean condition. If trims normalise at higher RPM, the leak is only significant at idle vacuum.
5. If no vacuum leak or MAF issue is found, check fuel pressure at idle with a fuel pressure gauge. Low fuel pressure at idle but normal pressure at higher RPM can indicate a failing fuel pressure regulator or weak fuel pump.

I costi di riparazione di P2187 variano a seconda della causa principale e del tuo veicolo. Ecco le stime tipiche:

P2187 si comporta in modo diverso a seconda del tuo veicolo. Seleziona la tua auto qui sotto per cause specifiche del modello, problemi noti e stime dei costi adeguate:

Questi codici compaiono spesso insieme a P2187 o indicano problemi correlati: