2006 gmc Sierra sle 5.3 engine 4x4. Have changed wires and plugs, mass control sensor, 4 o2sensor. Still reads lean on rt and lt bank code po 174,po300,po101
P0174 is usually a vacuum leak downstream of the MAF sensor. P0300 is a misfire, and P0101 means that there is a problem with the Mass Air Flow (MAF) sensor or circuit. After you replaced the sensors, did you remove the negative battery cable for 20mins and or clear the codes?