1990 Chevy Suburban idle/accleration problems

[SoCalSlaughter]

Hey guys, i have a 1990 Chevy Suburban with the 5.7 350 TBI, and I'm about to pull my hair out with this truck. Its been running bad like this for almost a year. It has a really hard time accelerating from a stop and when its warmed up the idle wants to shoot to almost 2,000 in P. I also noticed while Im driving the IAC will whistle like a turbo when I let off the gas and at a idle I can hear it sucking in a bunch of air. Sometimes I get a engine light but it always read "Lean". Sometimes when its cold it runs like a camp, like nothing is wrong, but after awhile of coming to stop signs it starts to do it again. Most of the motor is new and new sensors and ignition. Replaced intake manifold gaskets, egr gasket, valve cover gaskets. I noticed that the PCV valve vibrates very quickly even when I pull it out of the valve cover still connected to the TBI. And the timing is dead on. Since I've had the truck (Got it with 113,000. now at 141,000) Ive rebuild the TBI, intake manifold gaskets, new distributor, preformance ignition system, all new gaskets, all new sensors, fuel filter. Im thinking dead cylinder or burnt valve.