P2179 Fault Code

System Too Lean Off Idle Bank 2

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

The P2179 fault code indicates that the Engine Control Module (ECM) has detected a condition where the fuel-air mixture is too lean on bank 2, particularly when the engine is off idle. This situation typically occurs when the air-fuel ratio is not optimal for engine performance, leading to inefficiency and potential engine damage if not addressed.

What are the symptoms of the P2179 code?

Common symptoms associated with the P2179 fault code may include:

• The check engine light being illuminated
• Poor acceleration and reduced engine performance
• Rough idling or stalling
• Decreased fuel efficiency
• Possible engine misfires

What causes the P2179 code?

Several factors can lead to a lean condition on bank 2, including:

• Vacuum leaks in the intake manifold or hoses
• Malfunctioning fuel injectors
• Clogged fuel filter or fuel lines
• Failed oxygen sensors
• Exhaust leaks which can influence the readings of the oxygen sensors
• Faulty Mass Air Flow (MAF) sensor providing incorrect air measurements
• Issues with the engine's fuel delivery system

How to fix P2179?

To resolve the P2179 fault code, the following steps are suggested:

• Conduct a thorough visual inspection of the intake system for any visible leaks.
• Test the fuel delivery system, including pressure tests and injector function checks.
• Replace or clean fuel injectors if they are found to be malfunctioning.
• Inspect and, if necessary, replace the MAF sensor and oxygen sensors.
• Clear any trouble codes and conduct a test drive to ensure the issue has been resolved.