mark weldy

hello all,

ive viewed several forums and ive seen similar issues, but not all that i am having, so hopefully someone has been where I am currently

bought a used 2001 suburban 1500 2wd. only problems it had( when i test drove it) was instrument cluster,gauges didnt work or acted funny(googled new panel it was only $100 so figured not a big deal).also it was sluggish when giving it gas. gas gauge said low fuel, and i figured it had been sitting so just needed fuel filter and fresh gas.

originally when i had code scan:
po354
po356
po449
po452

next day code scan:
po161
po304:
po354
po356
po449
po452

during this time i started experiencing dead battery in morning, or after day of work.
replaced battery
replaced alternator
every 3rd to 6th week, i experience dead battery.currently in 8th week without dead battery issue

i replaced coils
i replaced spark plugs(verified gaps)
i replaced plug wires
oil change
air filter change
fuel filter change

codes remained
i went ahead and bought a plug-in bluetooth scanner.......partial instrument gauges returned to normal LOL

driving under 50 mph i definitely notice sluggishness. over 50 not really noticable

before i start replacing things one by one and hunting this down with $$$ does anyone have any ideas please.

Thank You