Just so we don't repeat anything that you have replaced already......
parts replaced fuel pump, filter unknown miles on that . plug wires, plugs, air filter , new tps. has different mass air flow sensor .
How old is the O2 sensor
When you take off from a stop do you notice any hissing sound coming from your cat converter?
A bad O2 sensor
would decrease power and a plugged cat would also.
But since you said it loses power after its warmed up then it could also be a IAC sensor
ontrol Valve )
will affect the way the motor runs when its going bad.
Do a quick test the next time it acts up. Pop the hood and tap on the IAC sensor
to see if engine power returns for a sort while.
Look for the sensor on your throttle body that looks like this where it plugs into the wire harness to find it:
What brand of fuel pump
did you have put in?
The only reason I ask is because a bad fuel pump
would also decrease power when its warmed up as well.
Have you checked your fuel pressure when the motor acts up?