Changed both 02 sensors and reset the codes. Drove 105 miles shut vehicle off for one hour came back out started truck and light came on in three minutes later.
P0171 Fuel trim lean Bank 1
After driving the vehicle, then a restart, So the code was pending during your driving, and the restart made the code come to full maturity, Check for vacuum leaks especially the PCV hose making sure its not collapse, and do a MAF cleaning, Another big part that causes a P0171 is sparkplug wear, A worn sparkplug where the sparkplug gap is over this will set a lean code.
Even though your engine may require a platinum type of sparkplug, they do wear out,
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