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The 300's codes are for engine misfiring ,the code P0171 is a lean code ,the engine is running with the wrong mix(air/fuel)
The most common problem for the lean code is a vacuum leak,i would check for any broken/disconnected vacuum hoses.
The Mass Air flow sensor is another possible problem that sets the P0171 and also can create this misfiring codes.
The fuel pressure or poor quality gas (water in the gas) is another possibility.
Do you feel the engine running rough ?
Have you try to clear the codes and drive the vehicle again to see what codes comeback?
Let me know.
Thank you very much.
Ok, so you do have a misfire ,can you read the codes to see what comes up first?
This is the 4 cylinder engine right ?
Hi there...sorry for the wait.
Scan the engine again to see what codes came back, if you have just 1 or two misfiring codes ,swap the coil from the bad cylinder with another cylinder that is working.
Clear the codes and run the engine again, if the code changes to the cylinder you put the possible bad coil ....you know you need a new coil , if it stays as the same code...check the spark plug, if good...you will need a new ignition module , located on passenger side by the air filter box,it has two connectors to it and is secured with two screws.
Hi there, I am glad you fix the problem.
Like I said on my first post ,the P0171 is for lean code and the most common for lean code is a vacuum leak , it must be a pretty large vacuum leak to make the engine misfire that bad.
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