Accelleration Hesitation at 1500 RPM

HELP. I've been struggling with a problem with my 2004 GMC Yukon with a 5.3L V8. When I accelerate from a dead stop, my engine "gurgles" at 1500 RPM and hangs. Then I'm at the mercy at whatever happens next. It can simply just not accelerate and leave me coasting at an intersection or finally decide it should pickup and accelerate to get me out of harms way. I've already replaced the MAF, the throttle-body, the EVAP canister, the EVAP solenoid, Corrected an H02 sensor code by replacing the Bank 1 Sensor 1 which cleared the ODB2 code and happened to replace the FuelPump because the fuel sensor float wasn't working.

So I have a ODB2 code free car and it still hesitates (nearly stalling) at 1500 RPM when I accelerator from a dead stop. It is almost as if whatever happens before the car shifts from 1st gear to 2nd gear is causing the problem.

HELP. I don't know where to start next in my troubleshooting