1997 ford f-150 5.4L V-8

Question

engine codes, po171,po174,po136,po401,po402,p1131,p1151,p1406.

Answer 1

P0171 Fuel trim lean Bank 1

P0174 Fuel trim lean Bank 2

P0136 Oxygen sensor circuit low Bank 1 Sensor 2

P0401 Insufficient EGR flow

P0402 Exhaust gas recirculation excessive flow detected

P1131 Lack of upstream heated 02 sensor switch

To resolve the code condition resolve the lean condition, The lean codes are mostly from vacuum leaks that upset the fuel to air ratio, Because there is a EGR code, that should be checked for being stuck in the open position

​ Here the EGR is partially stuck in the open position this cause a leam code condition