P0174: System Too Lean (Bank 2)
MediumPowertrainFuel Metering
What does P0174 mean?
P0174 is a diagnostic trouble code indicating "System Too Lean (Bank 2)". The engine is running with too much air relative to fuel (lean condition). This can cause hesitation, rough idle, and potential engine damage if left unaddressed. The fuel metering needs attention.
Common causes
- Vacuum leak (intake gasket, hose, or PCV valve)
- Weak or failing fuel pump
- Clogged fuel injectors
- Dirty or faulty mass airflow (MAF) sensor
- Exhaust leak before the O2 sensor
What should you do?
Schedule a diagnostic appointment at your earliest convenience. The vehicle is generally safe to drive short distances, but the underlying issue should be addressed to prevent it from worsening.
Get a diagnosis for YOUR car
Code P0174 can mean different things depending on your vehicle. TorqueBot gives you a diagnosis specific to your make, model, and year.