P0174 Fault Code

System Too Lean (Bank 2)

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0174 fault code indicates that the engine's computer has detected a lean condition on Bank 2 of the engine. This means that the air-fuel mixture is too lean, which often leads to performance issues and increased emissions.

• Bank 2: Refers to the side of the engine that contains cylinder 2.
• Lean Condition: Occurs when there is too much air or not enough fuel in the combustion mixture.
• Impact: Can affect overall engine performance and fuel economy.

What are the symptoms of the P0174 code?

Drivers may notice various symptoms that indicate a P0174 code:

• Rough idle or stalling
• Decreased power or poor acceleration
• Hesitation during acceleration
• Check Engine Light or Service Engine Soon light illuminated
• Increased emissions or fuel consumption

What causes the P0174 code?

Several factors can lead to a P0174 error code. Common causes include:

• Vacuum leaks in intake manifold or hoses
• Faulty mass airflow (MAF) sensor
• Dirty fuel injectors
• Weak fuel pump or low fuel pressure
• Clogged fuel filter
• Exhaust leaks before the oxygen sensor
• Issues with the engine control unit (ECU)

How to fix P0174?

To resolve a P0174 code, follow these steps:

• Inspect for vacuum leaks, including hoses and the intake manifold.
• Clean or replace the mass airflow sensor if it's dirty or malfunctioning.
• Check fuel pressure and ensure that the fuel pump and filter are working correctly.
• Clean or replace clogged fuel injectors.
• Examine the exhaust system for leaks before the oxygen sensors.
• Reset the ECU and perform a test drive to confirm the issue is resolved.