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1995 Chevy PU sputtering

1995 Chevy Silverado, 3/4 ton, 350 motor, 4x4. Was running fine started acting like it wasn’t getting fuel. Changed fuel filter, no change in behavior. Would a bad alternator cause rough running? Help.

No the alternator won’t usually cause rough running. What about the fuel pump? HOw do you know if it is putting out what it should? You can get a pump tester pretty cheap at checker, auto zone, etc. There is a valve on the fuel rail to test the pressure. Other things to look at is a stuck EGR, does it miss? Is there a Vac leak? It could have a bad injector, is it single point or throttle body? If it is throttle body, you can look down the throttle body and ensure both injectors are providing a fine spray, not a dribble when the throttle is opened.

It seems to miss or not getting enough fuel, I’m not well versed enough to know the dif. If I am patient with it and hold the throttle down it will sputter and fight until it finally allows me to rev it at a higher RPM. Then it starts all over again. when I put in drive it just fights and sputters. It has a throttle body, I’m going to check now about fuel spray. Where is the EGR? Can you plz give me more info on how and where to check the fuel pump? Would I be checking the fuel rail on top of the motor or underneath the chassis? thx for your help. When it did this last time it was the fuel filter, I changed it out and it fixed it immediately. That didn’t work this go round.

call me if you can I’ll go over some of the things for you to check. 801-540-6057

There are alot of possibilities, but my thought would be fuel injectors. Some sea foam may offer a little improvement, but it is really time for a proper diagnosis, and that is impossible to do online.

this model does not have a schraeder valve in the fuel rail. It’s throttle body. Gonna have to test fuel pressure at filter. 9-13 psi is specs. Most common problem is split hose between pump and pipe.