Hi guys, had a problem and solved it- just wanted to post up the experience in case someone else gets the same thing.

96 F150, 302 4r70w 4X4, 130K. Tuesday afternoon, out on the road, she shot me a code. Ran just like always. When I went to leave, started and ran fine, code gone.

Went to leave work Thursday night, and she stumbled BAD off idle. When I drove in, there was no trace of this, it came on like flipping a switch. Never died, but it sounded like it would every time. Good power on the other side of the stumble, and if I went from idle to full mash throttle, it either didn't happen, or was so short it was unnoticable. Didn't think it was a fuel pump, but I switched tanks to verify, and it followed to the other tank.

I'm thinking TPS, but there was no code at all, so I didn't want to start making 50 dollar guesses. Got out this morning, and got to checking my vacuum hoses. I found a bad hose leading to the throttle body, and replaced it.

The problem was still there. I checked for other vac leaks, and found none. I pulled the hose off of the booster, and squirted a little carb cleaner into the hose. I repeated this several times, and the problem went away.

Obviously, It's time for another round of Seafoam (It's been a few months).

I'm mostly posting this so that someone else having the same problem can possibly save time and money from my experience.

My only question is: Does anyone have any ideas as to what was dirty that the carb cleaner took care of? I can't imagine it being an injector, since it's a multiport setup. I'm just curious at this point, as baby is running right again.
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Hard to say what it was or if the carb cleaner just caused the computer to adjust, with the sudden rich exhaust stream (unburned due to cleaner), and set some different parameters. Most likely since your truck is a 96 and has SFI (Sequential Fuel Injection) I would guess that you have an OBD-II computer system and would therefore try to recover the code that set the Check engine light just so we know what the computer didn't like and then go from there.