Code P0171

ALIJAMAL

MEMBER
2007 HUMMER H3
88,000 MILES

HI thanks for reading I recently got the code
freeze frame info
DTC P0171

Fuel SYS1 cl

Fuel SYS2 N.A

Load PCT calculated load value 18, 0%

ETC engine coolant temp 86 C or 187 F

Short term fuel 1, 6%

Long term fuel 24, 2 %

Map 29 KPA

RPM 601 RPM

VSS Vehicle speed 0

spark advance ignition timing advance 10

IAT intake air temp 57 C

MAF 3.00 g/s

TP 12.2 %

Air Stat off

P0171 engine runs too lean B1 S1
any way no vaciom leaks found after I changed the intake manifold still the same problem
today I changed the exhaust manifold due to crack with new OEM new one I have reset the code p0171 now the trem fuel level is like

Short fuel trem is 7%
long fuel trem is still 24% just like old times
HO2S sensoer changed by new one code is still there

i am going crazy I already through 740$ for exhaust manifold 250$ for intake manifold 65$ for HO2S 95$ for MAF its driving me crazy please help

hummer h3 89000M 2007 LLR 3.7l I-5

no miss fire records on cylinders

Correct me if I am wrong

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

An engine can run lean due to a number of reasons.
It could be due to an intake leak, vacuum leak, exhaust leak, faulty mass air flow sensor, malfunctioning oxygen sensor, it can also run lean due to a leak in the air intake tubing.

The best course of action would be to take a look at the usual possibilities and take appropriate action.

Here is a helpful guide:

https://www.2carpros.com/articles/repair-lean-mixture-codes-p0171-or-p0174-on-some-manufacturers

Since you have already checked and replaced a few items it is a good idea to take a deeper dive of that code diagnostics.

I have attached the troubleshooting steps for Code P0171 below for your reference.

Please let me know if you have any questions.
Thank you.

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