Question about 2002 GMC Sierra 1500

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Odb2 reading codes p0171, p0174, p0300. running lean, multiple misfires. what coul be causing this? I know i need to clean the k&n filter.

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  • In the vast majority of cases, simply cleaning the MAF sensor does the trick. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling
  • Inspect all vacuum and PCV hoses, replace if necessary
  • Check for a dirty fuel filter and proper fuel pressure
  • Posted on Dec 11, 2009

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    no dtc definition found
    EGR FLOW insufficient

    Posted on Aug 24, 2010

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    Check the dist.cap and wires

    Posted on Dec 12, 2009

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    SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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    SOURCE: shake rattle then roll. rough idle last few weeks

    The intake manifold gaskets are the most likely cause of your problem. Have the fuel pressure tested also.

    Posted on Jan 04, 2010

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    SOURCE: my engine light is on

    This is sign of a vacuum leak (possible off of the PCV system). This causes additional air to be introduced into the engine causing the fuel mixture to lean out. With the engine running, shoot short burst of starting fluid around the vacuum lines. When the engine revs briefly, you have found (at least one of) your leaks.

    Posted on Jan 07, 2011

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    SOURCE: 2002 gmc sierra p0171 p0174 p0300 oygen sensor and

    Check for vacuum leaks to start. Then check the evap system. I just replaced a evap vent solenoid on a suburban with the same codes. fixed the problem.

    Posted on Apr 17, 2011

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    I have 2 codes p0300 and p0171

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    System to lean bank, manufacturer control fuel air metering, cylinder misfire detected

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    2012 Nissan Versa 1.6, after idling for a about 20 minutes (or while in heavy traffic) engine starts sputtering and eventually would stall. Would no start till cooled off. The following codes come up :...

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    Multiple engine codes 2002 tribute. p0171, p0174, p0300, p1401

    I doubt it.
    Codes 171 and 174 are for lean fuel mixtures, 300 is for random missfires which could be fuel or ignition related, and 1401 is for a problem with the EGR valve system. Now the EGR could cause the other codes if the valve is open or leaking when it should be closed.
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    2003 Ford Ranger 4x4 extended cab- diagnostics checked and got these codes- P0171, P0174, P0300, P0316. Can you tell me what they mean?

    P0171------ system too lean bank#1
    Po174------ system too lean bank#2
    For these 2 codes, try cleaning the maf sensor (mass air flow), that is mounted in the big black hose that goes from the air filter housing to the throttle plate, if it is dirty, that will cause those 02 sensors to send a signal to the computor to lean the air fuel mixture. If cleaning it doesn't work, the sensors will probably need changing.
    P0300---- Random/multiple cylinder misfire
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    On those 2 codes, you have to do some testing to find out why there is a misfire.
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    fowling spark plugs/wires
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    Have code P0001, P0171, & P0300. Need to know

    P0300 Random/Multiple Cylinder Misfire Detected
    P0171 System too Lean (Bank 1) - Read Our Article On Oxygen Sensor Codes For Help With This Generic Check Engine Light Code
    i could only find the 2 codes for you
    try here
    what kind of shape are your plug wires in ?

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    Check engine light on,running rough and stalling.

    means you have multiple misfires (po300) the other codes are lean codes, possiable tune up , bad injector, fuel pump,

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    Lack of fuel when accelerating

    This might help. It looks like you O2 sencor had gone bad or the signal has and causing multiple mis fire. according to your codes. 
    PO171 System too Lean (Bank 1

    PO174 System too Lean (Bank 2)

    PO300 Random/Multiple Cylinder Misfire Detected

    Causes of PO300
    Fuel injectors, related wiring, sensors and computer issues
    Running out of gas, or poor fuel quality
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    Incorrect Fuel Pressure
    EGR system concerns

    I'ld start with chaning the O2 sensors first but sheck for bad wire connection. Hope this helps and good luck

    Apr 08, 2009 | 2004 Ford F150

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