1997 f-150 missing on acceleration and a pop(backfire) sound to..

[x1957x]

Have a 97 ford f-150 with a 4.6cu. and when it gets warm it has a tendancy to get sluggish and like a miss on a slow acceleration when going 50-60mph. Though when I step it down it seems to have power.. Now it sometimes pops like there's a possible backfire like a timing issue? Was thinking coil or gas.. I see tonight that the check engine light came on now. Any thought's are gretly appreciated!!

[Macgyver55]

Check the code now that the light is on, sounds like its probably a bad coil pack.

[Scott K]

Bad plug wires are common on the 4.6 in this era. I agree check the codes, it should point you to a cylinder.

[x1957x]

Checked out alot of things including plug wires. Coded up as #1cyl. but kept checking (persistant) and found out that it was the EGR valve. Changed it out and it runs fantastic! Thanks guy's for the advice..