What P0174 means
The same lean condition as P0171, reported on Bank 2 of a V-configuration engine: unmetered air or under-delivered fuel on that bank, with the computer's correction maxed out. Alone it points at Bank 2's plumbing; paired with P0171 it points at shared systems.
What you’ll notice
- Check engine light
- Rough or surging idle
- Hesitation under light throttle
Likely causes and repair cost
Broad US independent-shop bands, parts and labour.
Can you drive with P0174?
Same as P0171 — drivable, but sustained lean running is hard on the engine's hottest parts. Prompt diagnosis over parts guessing.
The misdiagnosis to avoid
Diagnosing it in isolation when P0171 is also present. Solo P0174 justifies searching Bank 2's gaskets and hoses; the pair means one shared cause, and hunting each bank separately doubles the diagnostic bill for the same hole.
Describe what it’s doing in your own words and the symptom checker gives you a safe-to-drive verdict, ranked causes with costs, and notes to take to the shop — free, no sign-up.
Read the code yourself
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Check price on AmazonQuestions people ask
Which side of my engine is Bank 2?
The bank not containing cylinder 1 — and where cylinder 1 lives varies by manufacturer. On many V6/V8s Bank 2 is the driver's side but on plenty it isn't; check your engine's layout in service data before buying anything side-specific.
Intake manifold gaskets keep coming up. Why?
On many V-engines the manifold sits between the banks with long gasket runs that harden with heat cycles and leak at the ends first — which shows up as lean codes, sometimes one bank before the other. It's a known pattern on enough engines that shops check it early on lean pairs.