P0174 - System Too Lean (Bank 2)
Plain-English meaning
The engine control module (ECM) has detected that the air-fuel mixture on bank 2 is too lean, meaning there is too much air and not enough fuel.
What to check first
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What not to replace yet
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Stop driving when
If the vehicle experiences severe hesitation, stalling, or loss of power that affects safe driving, stop driving and seek professional assistance.
Related symptoms
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Owner steps
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Likely causes
Vacuum leaks on or near bank 2 (medium)
Faulty or dirty mass air flow (MAF) sensor (medium)
Clogged or leaking fuel injectors on bank 2 (medium)
Weak fuel pump or low fuel pressure (medium)
Faulty oxygen sensor on bank 2 (medium)
Exhaust leaks near oxygen sensor on bank 2 (medium)
Shop steps
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Follow-up questions
When did the check engine light first come on?
Are there any recent repairs or changes to the intake or fuel system?
Is the vehicle experiencing any other symptoms like stalling or poor acceleration?
Has the fuel filter been replaced recently?