bogginblazer

ok i got a 2001 chevy 1500hd 200k

i got this guy a month ago. it runs and drives but cant do a burn out and just does not have the go power a 6.0L should.

so both banks are running lean. the codes po171b po174b.

when i start her up in the cold chicago morn it has a huge miss runs really ruf. it has died at idle a few time on me in the morning. i have put new plugs in it. the wire are newer. coil packs are good. i dont know where to go from here the oddest part i have no po300 code.

please help

thank anyone for there help