1989 Toyota pickup 22re

[CaseyS71]

So I have a 1989 Toyota pickup with a 22re, and im having a problem with the engine bogging out if I press the gas pedal more than a half inch or so, revs fine when I barely touch the gas but any more than that and it tries to die. I've already replaced the fuel pump, circuit opening relay, fuel pump relay, throttle positioning sensor, and I've already tested the MAF sensor, any help would be appreciated, thanks!

[Snowtoy]

Timing, distributor, ignition, intake leak, would be where I would have started. 

Is the truck new to you, or did this come out of the blue?