Found a nice big vacuum leak at the egr valve tube going into the s/c. I went ahead and just removed the entire egr crap. I'll just have to deal with the CEL until Justin gets a chance to tune out the egr for me sometime later. Hopefully this will take care of my p0300 misfire code. I still don't think this is what's causing bank two to run lean. I haven't driven it around yet to even see if it took care of my random misfire dtc. I'll find out tomorrow.
Oh yea, btw. I further disassembled the old 5.3 and found 3 melted pistons (pistons 2, 4, and 7), a crack in the number 7 cylinder wall, and a blown head gasket. Found some of the missing pistons melted to the heads. Apparently, my lean issue started with the 5.3 from what it looks like.
Further evidence to run AFR gauge on both sides of the exhaust? ....wow, that's nuts.
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