i have a 2000 ss 96k miles on it...

recent work done was-
clutch
tranny rebuilt
walbro 255 fuel pump
and a retune because it lost it's tune

my problem started out as a hesitation... right after filling up the tank... then turned into hesitation problem when starting after it was driven and reached operating temp... by hesitation i mean a stumble... the gas pedal was in and it was like it wasn't giving it fuel then something 'clicks' (figure of speech no actual clicking) and it drives normal... now it turned into gas pedal 1/2 way in and the car doesn't do anything it sits there like it's idling??? any ideas also if more info is needed let me know...

last thing to injectors are maxed out at like 105% i don't know if it'll affect it or not thought i'd throw it in there

 

How did it lose it's tune? Someone playing games and erased it on you? It won't lose a tune, you can remove the engine computer for 100 years and when it's reinstalled it will still have the tune in it.
Whats the fuel pressure reading?

 

+1 on fuel issue

 

fuel pressure reads 58 psi... that's the thing it doesn't do it while idling i need to get a gauge i can use while driving it... and no not playing games very trustworthy tuner, he said he had another customer with an ls7 whose battery died in a weird way that it erased the tune also... please don't bash my tuner/friend i know it might not be your intention but thanks for the help anyways

 

All I'm saying is an untouched computer will not lose it's tune. It can if something happens DURING TUNING. But a car sitting, an engine computer sitting, will not lose a tune.

A battery dieing while writing a tune to the VCM (engine computer) can screw it up.
Not to bash your tuner/friend, but maybe he's doing something thats causing problems like this. If no one points out the problem, no ones going to look, and the problem will keep happening, so realize I'm trying to help.

 

maybe throttle position sensor