New guy here, but not my first 4.3. I have done quite a bit of work on this truck in the last few weeks, but it is still presenting this problem.

It starts right up and runs fine. The first time you go to take off, it acts like you aren't giving it gas. After that first takeoff, it seems to work fine.

Also, stutters and sputters when you turn the wheel hard, especially in reverse.

I have already replaced, plugs, wires, cap, rotor, and fuel filter. I have a new fuel pump that will be installed this week, but I don't think that it will fix the stuttering turn.

If anyone has a clue about this, that would be great. I have had s-10's, sonoma's, and astro's, and never come across this issue.

 

Fuel delivery is where I'd look, regulator, filter. Turning while in gear especially if you go full turn taxes the engine & PS pump so that slows the engine down. Reverse has higher gears so the engine is taxed more at steering wheel lock up when you give it gas.
Maybe try some fuel line cleaner as a "quick fix" test. But "search" for Kyles (swartlkk)<--- (he's the head honcho) fuel pressure posts on what the pressure should be & whats in the norm for it dropping down. I think the lines should have 50 or so psi & drop down to 35-40 psi.
Check out https://blazerforum.com/forum/engine...61/#post467891 he has similair issues & may be common

 

Replaced the fuel pump today and it cleared it all up. I was pretty sure that was the problem, just thought i'd check before wasting the time. Now off to fix the ragged suspension......

 

Hey Bud, Just wanted to say welcome to the site & it's nice to see someone else on the site w/ a 99 Bravada to for a change. lol We're kinda like the redheaded step children of the "Blazer World" lol