What does code P2179 mean?

Q: What does code P2179 mean?

System Too Lean Off Idle (Bank 2). P2179 means the engine computer has detected a lean condition on Bank 2 that occurs only when the engine is off idle, meaning the fuel mixture contains too much air and not enough fuel under load or above idle speed. The powertrain control module compares oxygen sensor feedback against expected fuel trim values and sets this code when Bank 2 fuel trims exceed the calibrated lean threshold while the engine is above idle.

DTC codes / P21xx · Fuel and air metering / P2179

P2179System Too Lean Off Idle (Bank 2)

P2179 means the engine computer has detected a lean condition on Bank 2 that occurs only when the engine is off idle, meaning the fuel mixture contains too much air and not enough fuel under load or above idle speed. The powertrain control module compares oxygen sensor feedback against expected fuel trim values and sets this code when Bank 2 fuel trims exceed the calibrated lean threshold while the engine is above idle.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyProfessional

AreaFuel and air metering

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.