[fuzzypuppy]

If the check engine light comes on while the truck is running there should be some code to read, but if the light comes on after the engine has died it is normal.
you need to be a bit more spefic on what happens when it dies or idles rough, but the first thing I would do the next time it happens is pull a plug or two to see whats happening, fuel soaked=bad spark or bad fuel delivery, black fluff = running rich=possable bad o2 sensor or temp sensor, etc,
with the information given I couldn't even guess, it could be many things, Egr cat, repost with what you find.
to retrieve trouble codes you jumper the two far right terminals of the plug screwed to the underside of your dash drivers side with the ign key off, "I use a paper clip, I always carry one in my truck for just such an emergency", then turn the key to on and watch your check engine light, it should flash once then pause then twice "a 12 code", it will do this 3 times, this indicates your in diagnostic mode, keep watching your light and it will flash a code such as 4 blinks pause then 2 blinks, it will do this 3 times as well "a 42 code", if there are other codes it will then flash these 3 times for however many codes there are set, after give'ing all the trouble codes stored it will then again flash a 12 code.