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UPDATE:
Here's what I did today:
Clear codes.
Drive it.
-Codes came back, same.
Watch stoich levels during limited boost rise.
-Was a little rich, not 10, more of a 12.5.
Check MAF voltages when running.
-All normal.
Check coolant temp sensor warm resistance.
-Normal per FSM.
Listen to idle, pull injectors one by one. Listen for misfire, NOT just a drop in rpms.
-Drop in RPM occurs with every injector and coil pack disconnected. Cylinder 4 was the only one that, when removed from the drive train, did not stumble. When the suspect cylinder was still in the drive train, it would stumble down to 2 cylinders. This leads me to believe that my issue is either spark or fuel in cylinder 4.
Pulled coil pack 4 and spark plug 4. Swapped with coil pack and spark plug from cylinder 2.
Check coil pack resistance.
-All normal per FSM measurements.
Rough idle is way less noticeable, and the stumbles were further between. So much so that when i removed cylinders 2 and 4 from the drive train, could not notice the stumble. Read a little bit about similar issues. Discovered the ability for the coil pack to become weak(sometimes spark on a big gap, weak spark with boost, or no spark with high boost), and not completely fail(no spark at all). I remembered re-gapping the plugs during the first day as part of my troubleshooting (.036, as per the FSM). Apparently when I introduced more boost, at a fairly "normal-large" gap, the coil pack couldn't create the spark, and fried itself. Not noticeable with FSM checks of resistance, or continuity with grounds.
MAYBE that gap was a bit much, considering some guys run a .028 with boost levels in the 12-15 psi range.
Plugs regapped.
IT CREATES BOOST!!!
ok, only the normal 7-9 lbs, and it still breaks up a little above 5 psi..
Replace fuel filter
-Needed it, and wanted to check it off my list.
Replaced spark plugs.
-Again, needed, and wanted to check it off my list.
Should be getting 2 known good coil packs tomorrow. Will swap it out with my suspect one, and then I will repost and update.
I'm seriously hoping it's just a bad coil pack. I've also got a known good fuel rail and injectors that I might swap in if the coil pack doesn't fix it.
Thanks for all of the input guys, I appreciate all your help.
Jake
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