How bad is it stumbling, because it will stumble a little when the compressor comes on but should not drop below 500 and if it does it should come back up to 600 where it should normally idle.

It's the same as when it missing, also back doing it at 1500 rpm. I've tuned wrenches for a very long time and this is the strangest most frustrating thing I have ever dealt with.
It will run smooth then at idle and 1500 rpm it just has this stumble to it. I'm not sure if there are any sensors I may have not replaced as regard to the ignition system.

.Cheers,
R-

So today, I took my trailer to help a friend move and about mid day it started to miss buck and die, engine light on. So after on star check which provided no results, made my way to an autozone and scanner told me I had a p0300 which I simply don't understand. Cleared the code, it ran rough for a few miles and cleared up. Smooth no miss. Then as I pulled up at home the miss and stumble have returned.
W.T.F.
New: ac/delco parts
Iridium plugs, coils, pcv hose, air filter, cleaned T.B and MAF (twice), cam position sensor.
checked intake bolts, 02sensor, cat inspected, new battery terminals.

by by far the most elusive issue so far I've chased. I'm confused as to the random nature of the issue. It would seem that if it were a failing part that the symptom would be more consist. Seems to increase after it reaches normal op temp.
ive checked for lose wiring on everything as well as checked the ground locations.
the code reader isn't of much help much like the only local dealer.

The hunt continues,
cheers
R-

So after calling around it's harder than expected to find someone to do one. Finally called the one dealer in my area and they said they can get me in to have it checked out in about 4-5 weeks.

In the mean time, would'nt the head issue be more consistent and let random?

Still getting the p0300 today after clearing the codes.
thanks so much,
Cheers,
R-

Hi, coil leak, I'm not sure I understand. The Radiator is new and the air is ice cold. The coil packs are also just a few days old.
Today, I went out in the rain and it dint not stumble, no C.E.L. Smooth as glass.
I know it won't last but it is a nice break.

Please let me know about the coil leak ref.
thanks so much,
cheers,
R-

I was also thinking. When I checked my intake bolts it was cold, would checking them hot make any differace in anyone's opinion.

Thanks,
R-

So today Spike as ive come to call my h3,
sputered and died. After a few hrs in the sun I discovered that the gray wire on the map sensor was half broken in two.
I did a bandaid repair and it fired right up, no light no more rough idle. Purchased a replacement connector and so far no more issues.
Hope Spike stays happy a while.

Thanks to everyone for your input.
Just gos to show even after you call yourself checking stuff, always a chance you over looked something.

Cheers,
R-