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Posted By: Joeman New to the forum; smoke at start, swivels, and steering - October 03rd 2021 10:12 pm
OK, where to start...
I've got a '95 G20 with the 5.7 (350) and it always puffed smoke on startup and ran super rich. In my case the root of the problem turned out to be the TBI, with a little over 160K miles it was shot, when you goosed the throttle without the air cleaner on it the injectors had a pattern that looked like somebody giving a squeeze to a bottle of mustard, almost no atomization, when the engine was warm it would tolerate it without being visible but on startup you'd see just a puff.
My advice, find a mechanic you trust, unless you do your own work that is. The good news is all the parts are available to rebuild it, they're just a bit pricey! And we all know stock is just not all that much fun anyways & with the small block chevy platform the sky is the limit!
Welcome to the site ..... the gear heads will be by shortly ...

Again welcome
Originally Posted by Joeman
OK, where to start...
I've got a '95 G20 with the 5.7 (350) and it always puffed smoke on startup and ran super rich. In my case the root of the problem turned out to be the TBI, with a little over 160K miles it was shot, when you goosed the throttle without the air cleaner on it the injectors had a pattern that looked like somebody giving a squeeze to a bottle of mustard, almost no atomization, when the engine was warm it would tolerate it without being visible but on startup you'd see just a puff.
My advice, find a mechanic you trust, unless you do your own work that is. The good news is all the parts are available to rebuild it, they're just a bit pricey! And we all know stock is just not all that much fun anyways & with the small block chevy platform the sky is the limit!

I rebuilt the TBI on my 93 a few years ago. There is a kit available on Rock Auto. I replaced the injectors and fuel pressure regulator as well. I also added a step-up spring to the regulator to increase fuel pressure from 12 psi to 14 psi and a spacer block to raise the injectors up to allow a bit more air into the venturi area.
Yes, I think I looked at that kit, but I had Idle circuit issues as well. And that whole TBI thingy just looked like it had been through the wringer, maybe twice! And like I said earlier, I had head issues (burn't valves) and cracked exhaust manifolds. So I ripped the top end off & replaced it, Old School Style, new Promaxx aluminum heads, Stainless steel Shorty Headers, a nice set of 2-1/4" duals, Weiand dual plane manifold & a Holley 4bbl carb. It runs a bunch better and as an added bonus gas mileage is up from about 9 to mid 13's, I'm hoping to get MPG up at least into the high teens.
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