08 chevy silverado 5.3 back firing missing afm?

[99farmtruck6.0]

Hey GM guys 

 

I have a 2008 Chevy Silverado 5.3 im messing with right now.

Have a random misfire code and a LOUD tick Rev it up in Park it backfires thru intake real loud.. No power under load wont even spin the tires on slick concrete. 

 

Btw i thought it was an exhaust leak at first with a cpl o2 codes but o2 codes went away after I cleared them. Whats going on with this thing? 

[CamGTP]

What cylinders are misfiring?

 

Hard to really offer advice when we don't know that information.

[bg1988]

Could be the MAF sensor  they fail often mine would sit there and revv FULL throttle   in drive gear(without pressing the gas aka Engine run away)  by it self  but not move an inch

 

(back fired a few times when starting)

only way to know for sure is to look at the live data

 

 no issue with the transmission as everything is great again   with a new MAF/IAT sensor  

Edited May 25, 2020 by bg1988