P0174 — Fuel System Too Lean (Bank 2)

P0174 is the Bank 2 counterpart of P0171. It is set when the engine control module sees long-term fuel trim on Bank 2 driven beyond approximately +25 %. The ECM is adding the maximum allowed amount of fuel and the Bank 2 oxygen sensor still reports lean. Because P0174 only applies to V-engines and engines with separate exhaust banks, whether P0174 appears alongside P0171 tells you a lot about the root cause.

Severity: moderate powertrain Safe to drive (short term)

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2010-2014

2015-2019

2020-2024