Service engine soon code p0174 - 1999 Ford Expedition

Question edited for clarity. It is P-Zero 0, not P-oh O.
Please always include 'year make model' first 3 words, or it it is difficult to answer and some vehicles are slightly different or more precise and will show known issues.

P0174 - OBD-II Trouble Code Fuel System Too Lean (Bank 2)

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When a vehicle has the fault code P0174, it means that computer can no longer automatically adjust the mixture between air and fuel. Code P0174 applies to V ...

P0174 OBD-II Trouble Code: System Too Lean (Bank 2)

https://www.yourmechanic.com > Articles
Code P0174 indicates that there is a lean condition detected by the Engine Control Module (ECM). A lean condition will be created if there is too much air, and ...

P0151 Code - What Does It Mean & How To Fix It - OBD2PROS

https://obd2pros.com > dtc-codes > p0151
A P0151 code is caused by an ECM (Engine Control Module) receiving a signal indicating the O2 sensor for bank 2 sensor 1 has failed to increase the voltage ...

Code P0171 - System Too Lean: Symptoms, causes, common ...

https://www.samarins.com > diagnose > p0171
Jul 10, 2021 - The OBDII trouble code P0171 - System Too Lean (Bank 1) means that the engine air-fuel mixture is too lean, or there is too much air and too ...

The four digit codes are brand specific, but in general, the three codes mean the fuel system is too lean.
The most common cause is low fuel pressure.

Hi try this video it may help you find the fault it covers the codes on 4.0l engine. Ford Explorer 4 0L SOHC Rough Idle P0171 P0174 Lean Codes

P0171 System too lean bank 1
P0174 System too lean bank 2

Last time you changed your fuel filter?
Look for any vacuum leaks.

P0172 - Fuel Injection System Too Rich Bank 1 Symptoms - Engine Light ON (or Service Engine Soon Warning Light)
- Excessive Fuel Consumption Possible causes - Intake air leaks
- Front Heated oxygen sensor may be faulty
- Injectors may be faulty
- Exhaust gas leaks
- Incorrect fuel pressure
- Lack of fuel
- Mass air flow sensor may be faulty
- Incorrect PCV hose connec Possible solution Dirty air filter of faulty air flow sensor are common causes of the problem.

P0174 - Fuel Injection System Too Lean Bank 2 Symptoms - Engine Light ON (or Service Engine Soon Warning Light)
- Excessive Fuel Consumption Possible causes - Intake air leaks
- Front Heated oxygen sensor may be faulty
- Injectors may be faulty
- Exhaust gas leaks
- Incorrect fuel pressure
- Lack of fuel
- Mass air flow sensor may be faulty
- Incorrect PCV hose connection Possible solution Dirty air filter of faulty air flow sensor are common causes of the problem. Bottom line possible defective Mass airflow sensor and or O2 sensor in cylinder bank number two.

Hi, 1151 is an 02 sensor code, 1131 is also 02 sensor code,
0174 lean condition bank 2, and 0171 is lean bank 1. Either this is in need of a whosale of repairs or you have computer issues, From looking at the codes i would first do a complete tune up, Including wires, And inspect for a vacume leak before replacing any 02 sensors..
Take care

code P0171 P0174?? sorry these are not nissan codes but the code readers own codes so return to where the reading was done and ask them

p0174= too much oxygen. have your mass air flow sensor cleaned or replaced

My service engine soon light stays on. The vihicle shakes as it idles. It act it wants to shut off. What's the problem

P0174, refers to a lean condition of the engine....Possible causes would be a vacuum leak, clogged fuel filter, or a leaking intake gasket( this is the most likely cause because Jaguar has a service bulletin on this very issue). P0105, refers to a MAP sensor malfunction which could also be causing the P0174

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