Help! Very odd issue

I have a 2000 454 chev/auto/ac/ loaded. Since I bought the truck I noticed a slight hesitation at low acceleration, a cough of sorts. I worked at a Chevy dealership and no mechanic could ever find a problem or explanation. Every once in awhile it would fail to start. It would fire and die immediately. I could walk away for 10 minutes and it would be fine.

I had new fuel pump put in it, plugs, wires, cap, rotor, fuel filter, etc. Truck has 119K. However, problem was never solved. Bout every few months it would have an episode where it wouldn't start.

Recently, for the past two weeks, it is now so regular on almost a daily basis. I am getting 50 psi at fuel rail and it is maintaining pressure after turned off. Fresh fuel filter again. But yet, daily almost it will fire and die immediately. I can smoke a cigarette and come back and it will fire, but then run like ass kinda sputtering along for a short while.

Dealership I am at now sat on it for over a week and gave me the "cannot duplicate" crap and didn't involve hardly any effort. I really need to figure this thing out if anyone has had a similar issue. All ideas are more than welcomed.

that almost sounds like what my blazer was doing (yea I know different vehicle,engine,year ect. ect.) what I found was the wires going to the injector were wore out and when they would move it would die or not start. if you grab them when its running and move them around a little you might get it to duplcate your symptoms

so the feulrail is holding its pressure?
might be there's feul leaking through the injectors smothering the engine on initial startup but then again the dealer should've picked up on that

ok remember guys i had the same dam problem with mine.. 2000 chev 454!!!!!

i changed the fuel pump and all the crap you did too....

my problem went away once i changed all the power source wires going into the main fuse box under the hood... (from battery to box and so forth) dont know if thats your problem but it fixed mine.

once i took the old wires off the truck i stripped them and they looked ok on the outside but were very britle on the inside..

its cheap to try and hopefully that will fix it for you like it did for me

looks like chevy goes cheap on materials again....

Injectors are inside the intake on these motors.

^^^^^^^thats the way my blazer is also it's all in the plenum

I had a friend having the same problem, it was his cam shaft positioning sensor that was the problem.

sometimes my wifes thinks i have problems positioning my cam shaft.. i think my sensor is broke because it trys to slide into the wrong hole...

if you hit that hole it will really be lopey