Why is my 98 sierra backfiring and burning double the fuel

I changed the plugs and wires , oil and fuel filter on my 98 gmc sierra z71 k1500 with a 5.7

I had a wire on each side crossed over somehow and drove it before seeing the problem the second time looking .

Now it burns about double the fuel and runs like it's dieing on takeoff with a load on it , not to bad without a load , but it's backfiring and spits a d sputters on takeoff and with or without a load tries to and does at times shut off when taking off at a light . Pulling up codes low air input at MAF and cam shaft position sensor, I've changed the MAF but no change .