Try cleaning the MAF as you already plan. It only takes 10 minutes and be sure not to touch the wire with anything. Only use MAF or electronic cleaner. These things can cause some strange symptoms and not throw a code. It's easy to do and you have nothing too lose at this point. Another thought is are you sure its the engine and not a transmission problem? Also with the engine running remove one injector connection at a time and determine if all cyls are firing. I know codes should be popping up but that is not always the case. Make sure the zip tube (air intake tube)is fastened around the throttle body securely. Check especially under the throttle body. Sometimes the clamp will come part way off and air will bypass the MAF into the TB. A compression and or leakdown test may be in order as well. Just some off the cuff ideas. Good luck.

 

Just wondering if you've figured out what the problem was with the truck yet. Sounds like I have a similar problem to yours... And i've done everything you've done except the cats (I have less than 100K miles on mine).

 

try cleaning the throttle body?
maf sensor?

 

What did he ever come up with? Anyone know?