I will show you some tips and tricks I learned while fixing the lean codes on my 2003 Ford F150 with the 4.2L V6. A perpetual P0171 code was preventing me from passing inspection. (This is NOT a "Howto" video.) Also, the failure of the IMRC bushings could not be determined until after removing the upper intake manifold. Your lean codes could be due to other problems. In the end, I enjoyed doing this repair, and the truck is running well with no more DTCs. Thanks for watching! Buckwsr, Putting the "Do" into "DoItYourself."

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