New Member with ?????'s

[Rodeo Bo]

Hey, I am a new member and was wondering if anybody had any Ideas about What is happening with my 97 f-150.

1. It occasionally feels like it is dropping a cylinder when under a slight load. Large loads don't seem to effect it ( pulling a loaded trailer) but on a daily drive it might do it. One example is driving up hill, just b4 the trans shifts to a lower gear it feels as if I have hit a bump in the road, but instead of bouncing down and back up the truck seems to shift from front to back. It almost feels like some one riding your bumper has given you a light tap of encouragement.

2. Some mornings/afternoons the truck will crank but it won't hold an Idle for 5-10min. and occasionally it will hold an idle at about 500 rpm. This problem is hit and miss also, but It seems to happen more after a long drive 3-4 hours at extended speeds but only after it has set up for the night.

I have changed the plugs and wires on this truck twice. The last time I even changed the twin coil packs. (this seemed to help for a little while)
As for the not idling problem, it my go months without popping up again.

Oh Yeah! There are no dummy lights or codes being thrown out either...