hello all
92 camaro rs / 2000 chevy silverado hybrid

i have a stalling at idle or low speed issue i need help with. 92 camaro with a 2000 5.3 truck engine, 4l60e trans, factory ecm and harness for the engine/trans.
this issue has been around for a few months, but i know it's not the fuel pump, filter or regulator because i just installed a new aeromotive stealth 200lph fuel pump/hanger/sender assembly at the same time i installed an aeromotive filter/regulator assembly with pressure gauge (set to 59 psi to the fuel rail). engine also has new plugs, and i cleaned the factory 92 fuel tank vent cap thingy. it mainly happens when i come to a stop....all the sudden engine feels like the timing went crazy and it stalls....doesnt happen all the time and some times i can shift to park rev it up until it goes away. it's not throwing any engine codes as of yet.

past things i've noticed that could be related was driving about 55mph steady and feel a surging in the rpms also not very often, and sometimes under hard acceleration it sounded like the valvetrain was out of adjustment....rattling or valve chatter
any idea's what to check?

 

any 5.3 experts?