I had misfires and idle drops/surges when I first had the truck. After a bunch of testing it turned out my cap and rotor were shot, the contacts were sparking but not with consistent timing. Replaced those, went to time it and it was 5 degrees advanced, changed it to 12 and that helped a great deal. It still doesn't run completely correct but I think the TPS is on it's way out.

I can't help with the low idle as mine seems to run a little high at times. I see you inspected the spark and removed the entire distributor but did you take off the cap and rotor and check the contacts? I didn't see it mentioned and there's a good chance I missed it reading through quickly at work.

 

what was happening im having the same issue

 

I am having the same issues currently .. have changed damn near everything with new parts... I wish I could find a problem to solve and keep from going totally crazy .. ANY advice or things that you have tried.??