Alright I have a 92 Toyota pickup with a 22re

Here's the Problem- As of right now it idles fine, but when I give it gas it's spits and sputters and sometimes back fires. This is with a different computer than I originally had. With the other computer it wouldn't even run when I tried. i was like the AFM wasnt plugged in. it would start and run for a few seconds then die. I was pressure washing my truck when it finally stopped running. Before it wouldn't run the
problem was that it didn't have any power when I was passed 1/4 throttle (it did at 1/4 throttle and before) and it also had power at full throttle. (But not all of it) however if I unplugged the TPS it would have power all the way through the throttle but after 1/4 throttle the amount of power I had wouldn't change. It also died and would take a while to start back up and get running again if I got it wet in a mud hole.

Here's what I have done- I have changed every gasket on the intake. The head gasket only has 4,000 miles on it. Cap, rotor, injectors, wires, plugs, AFM, TPS have all been changed. ( TPS was adjusted correctly with a meter.) ignition timing is right. And both fuel and air filter changed.

Please help! I'm trying to see if someone has any idea before I pull the motor to check over everything with a fine tooth comb. I'm starting to think whirring harness. Thanks