Can anyone help me diag my 6.0

[Willyjr]

Once in a while it starts rough shakes some and it drive decent but I can give full throttle it makes it fall like the tranny kicks down to passing gear but my motor doesn't it may say 3000 rpm but it has no power but I can pedal it find the sweet spot and it will start building power like a turbo motor I rarely have much snap throttle response and the majority of the time there is no light blinking a code and when I plug into it it's giving me a maf circut code and I did find where some genius hillbilly wired a new plug in to the AC and my maf wires run right where he cobbed that stuff together so I gotta get to my buddies shop and let them dig into the wiring that's where my skill set ends

[Nick17]

I work at a GM dealer we get these a lot your gunna need to get is scan checked to see which cylinders have misfires (if you haven't already done so) because you may have a bad injector or along with that you may be getting too much fuel into one of the cylinders. An intake leak would only cause it to idle rough.

[Swimmer8366]

Check your fuel pressure as well these Chevy's are anal about the right fuel pressure

 

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[Nick17]

broken exhaust bolts usually wont cause misfires DO NOT over look a cracked intake manifold i know you said you replaced the gaskets but they are known for cracks spray the shit out of it sometimes they are hard to find but even the smallest crack can cause a miss check your egr line that goes into the intake they like to leak too 6.0 engines can be tricky.