What is the difference between P2177 and P0171?

P0171 is lean at all times. P2177 is lean specifically off-idle (during acceleration), suggesting a fuel delivery problem under load.

Can fuel injector cleaner help?

Yes — a good fuel injector cleaner ($8-$15) can fix partially clogged injectors causing lean conditions under load.

Medium Severity

Fuel System

Bank 1 runs lean specifically when off-idle (accelerating). This often points to a fuel delivery issue under load.

Common Fix

Clean injectors or replace fuel pump

Estimated Cost (DIY)

$15 - $300

Clogged fuel injectorlikely

Weak fuel pump under loadpossible

Air leak in intakepossible

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What is the difference between P2177 and P0171?: P0171 is lean at all times. P2177 is lean specifically off-idle (during acceleration), suggesting a fuel delivery problem under load.
Can fuel injector cleaner help?: Yes — a good fuel injector cleaner ($8-$15) can fix partially clogged injectors causing lean conditions under load.

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