2000 dodge ram idle problems

2000 Dodge ram 1500 V8 5.2 automatic. I am having a very similar problem with my truck. It started today. I was on my way to work when my truck stalled in a McDonald drive thru. It would not start back up. Just kept turning over and turning over. I pushed it out of the way and started to look for problems. I could hear the fuel pump come on, I had gas, no spark. I was thinking coil. But than I noticed the plug wire going to the coil from the distributor cap was corroded. I barley touched it and it fell apart. Anyway, I towed it home. Got all new plug wires, distributor cap, and rotary button. The distributor cap was all ate up inside, there were two points that were cut clean through and the rotary button did not look to good. What gets me is I did this about a year ago, luckily all all these parts where still under warranty, so nothing out of my pocket.

So after I installed the new wires, cap, and rotary button, I gave the truck a crank. It starts now but idles rough. Strange thing is Last year I took a trip to WV and on the way home it did the same thing. It would drive awesome on the highway but as soon as I let off the gas it wanted to idle real rough and wanted to die on me. The whole ride home. But once I got back home, the next day I started it up and was perfect. No idling problems until today and it is the same problem. When I start up my truck it does not idle right. It goes from 800 rpm down to 300 rpm and back up and down,etc. When I put it in gear and take off it spits and sputters but than its fine driving on the highway until I slow down to turn a corner or stop at a light. sometimes it dies but sometimes I hold one foot on the brake and the other foot I feather the gas to keep it running.

I just replaced the IAC (Idle Air Control Valve)
and the TPS (Throttle Position Sensor)
Still acting the same. I read on your post that your truck Idles good in neutral. Not mine. It idles rough in park, neutral, reverse, and drive.
any ideas would really help. and if I figure it out I will let everyone know.
Maybe my problem is something els. Spark plugs? coil? any ideas