If anyone has run into this maybe this will help '97 F150 4x4 work truck, 4.2, auto trans, almost 200k

Codes P0174 (lean b2), P0455(evap gross leak detected), P0401(low/no egr flow)

Checking found fuel trims at +25 B2, and +16 B1, koer no egr flow change h... Login to read more.