Engine Stalls during acceleration from a stop.

The van idles fine and at just under 1000 rpm. When stopped, or even in park in the drive way, when you hit the gas and push the RPM past 1000 it was pause and sputter a bit. Sometimes it will stall out, sometimes it will just hesitate. I have had a scan tool on it, and no codes are present. The SES Light never comes on, not even when it stalls out. I have replaced the Oxygen sensors (Upstream and Downstream), Coolant Temp Sensor, Air Sensor, Plugs and Wires, I have checked for vacuum leaks (with carb cleaner), replaced the gas cap.
Other Symptoms:
Terrible gas mileage (200 miles to an 18 gallon tank - If I am lucky)
Barely any power once the hesitation passes

Does this sound symptomatic of a vacuum leak? The lack of coding makes it hard to diagnose.