P0171, P0174 = ?

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Dec 25, 2007 | 03:17 PM

nightrunner

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Mr. Obvious

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From: Manchester, TN

P0171, P0174 = ?

i pulled these codes from my truck a few minutes ago.

P0171
P0174

what do they mean?
any way to fix them?

i have not changed or modded anything on my truck recently.

i just read the sticky and it says they mean

P0171 - Fuel Trim System Lean (Bank 1)

P0174 - Fuel Trim too Lean (Bank 2)

what is causing this?

any and all help is appreciated

Dec 25, 2007 | 04:15 PM

Mangled03gmc

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From: In a van DOWN BY THE RIVER

That means that the engine is running lean. Could be caused by a bad fuel pump, dirty injectors, vacuum leak, or pcv or egr valve.

John

Last edited by Mangled03gmc; Dec 25, 2007 at 04:37 PM.

Dec 25, 2007 | 04:34 PM

nightrunner

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Mr. Obvious

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From: Manchester, TN

i figured so. just wanting to make sure

any idea on WHY? i havent changed anything lately

Dec 25, 2007 | 05:52 PM

Daryl4.8

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From: Austin tx

Bank 1 and 2 change your O2s

Dec 26, 2007 | 09:48 AM

YenkoST

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From: GA

Another thing to change is the fuel filter.

Put some fuel injector cleaner in there, change the fuel filter out, erase the codes and if you still have the same problem....you need to check the fuel pump voltage and psi on teh fuel rails....make sure it ain't going out on ya.