I have a 1995 Tahoe After your warm-up I lose power and backfires under the hood. I change the spot plug ,wires ,disturbing cap, Rotary button, Fuel filter ,fuel pump ,Injectors And It still do the sa

You have a timing issue

A timing issue would also be present before warm up.

If its backfiring...the fault was already there evidence being a misfire or very rough idle in which case he will need to tell us the whole story about what the truck is doing before warm up

The truck runs perfect before its warm up no problems but after it warms up no power and when I push on the gas it back fires and cut off

Ok when I first got mines the distributor shaft had a crack in it causing the engine to lose vacuum which made it backfire ....you might check that.