Any help would be appreciated. I have 86 silverado, replaced 305 engine six years ago with 350. Started dying on me while driving, then very difficult to start, when it would start if you put it in drive or reverse, it would die again. had pick up coil, ignition module distr cap, ignition rotor, fuel pump carburetor and fuel selector valve (dual tanks) all replaced and same problem persists. Needless to say im out of funds and people I trust. Anyone had this kind of problem I sure would appeciate any input. Ive been towed twice cause just couldnt get it started again. It will drive fine sometimes like to the store, but when I get in to leave, it wont start or keeps dying when I put it in reverse or drive. I just feel like its something to do with fuel but no one seems to know. thanks a lot Paula

 

did you leave the fuel injection [throttle body] or did you change it to carburetor? did you leave the fuel pump system in the gas tank, or change it to inline fuel pump? this will help to figure out your problem? I am not a professional mechanic . but I have a GMC, and also had a similar problem. yes I also replaced everything, after breaking the throttle body I realized the INLET on the throttle body from the PCV valve hose was clogged. that was my problem.