what would cause codes p0171 and code 404 on my pontiac aztek on 2001 Pontiac Aztek

after changing the acm sensor,gas cap, and purge valve,also changed the plugs and wires

Asked by for the 2001 Pontiac Aztek
Code p0171 is usually caused by a vacuum leak somewhere on bank 1. Check gaskets, seals, and especially vacuum hoses for damage to cause this problem.