Misfiring on all cylinders..... Damn Mike.... You've got a real brain buster here... There is no reason to suspect the MAF sensor itself, is there? What do the plugs say, if anything? No need to pull them all since you have a miss on all cylinders. I hate this guesswork crap. When misfiring in park/neutral, can you give it slight gas and have the misfires stop? I wish I could stand and look at it with you. It'* always nice to see things in person.

Well I've tried two MAFs already.
I haven't checked the plugs yet..
If I give it gas in P/N it smooths out but I don't remember if the scantool stops detecting misfires.. I'll check that out.

I guess I would suggest looking at the plugs, or at least the front bank. Check wire resistances, as you already mentioned. You basically need to go over that thing with a fine-toothed comb.

Check battery voltage and alternator output. Maybe there'* something wrong with the power being supplied to the ICM. Look into it if you haven't already. Cars do weird things when the voltage or amperage being supplied is erratic.

Have you tried spraying the engine seals (Upper/lower etc) with TB or carb cleaner when it starts acting up to see if one of the gaskets may have gone?

I sprayed those surfaces with the maf cleaner(alcohol) since it was the only thing I had on hand besides brake clean.
I'll stop by an autoparts store today or tomorrow and grab a can of carb/TB cleaner and try that.

If you didn't notice anything with that..you probably won't with carb cleaner. Hmmm You've checked all the usual suspects.

Are you tuned for your TB and UIM?

I was thinking that maybe the alki was evaporating before it could really do anything?

The prom is tuned for the TB and HVII. I'm getting steady MAF values and my fuel trims are good. I had both the TB and HVII in my last car and it ran without issue.

Another thing I haven't checked yet is the PCM harness ground thats near the oil pressure sending unit..

It'* so odd that I would hardly notice a problem driving if it'* cool out and theres no traffic..
Its got to be something closed loop and load related. In P/N theres no load and during decel there is no load. As soon as I'm stopped or almost stopped in D and the engine is working agianst the converter, there is no problem. As soon as I give it gas, theres no problem.

Have you tried replacing the ignition control module? it'* the piece the coils sit on. i remember a buick with a 3.8 my father was fixing, and whenever it got warm, the chip would heat soak, and the car would start misfiring and would die. just a thought of something that it could be.

Yep, swapped ICMs. (it'* in the long list up top)

I assume you already checked battery and alternator output? Worth a shot, I say.