2004 chevy suburban P0172 code

What is your question?

I know it says it is running too rich. I replaced the MAF. I have had a random miss fire code as well. That went away when I replaced the ECM. I have replaced the spark plugs, wires, coil packs, crank sensor, the gas pedal, gas cap, and injectors. All of this was done prior to the ECM replacement. I have had all the grounds cleaned and tightened as well. Any help would be great.

What makes this problem better or worse?

Nothing

How long has your 2004 Chevrolet Suburban 1500 had this problem?

1 year