Try cleaning the MAF sensor. I can go 35 MPH easily without touching the gas pedal in my 03 F-150 that has a 4.6 L engine and automatic tranny. That's not unusual if you are coasting down from a higher speed. After you clean the MAF, and it still misses, then you need a general tune-up. That includes plugs and wires plus setting the timing to correct specs. Check the codes again to see what may be the problem.