91 mazda b2200 crank no start

I bought this 91 b2200 5spd carb a few months back and ever since it has sputtered worse and worse. When I give it gas or stop it stalls out sometimes. Well it stalled out on me while I was giving it gas, then it wouldn't start back up. I towed it home and changed the fuel pump (didn't need it) I changed the distributor cap and rotor and coil. I got it started with a little trouble then adjusted the idle screw and it was running fine until it started sputtering again and died on me at a stop light. couldn't get it started so I towed it home and now I don't know what the next step would be. HELP PLEASE

Keep in mind ive ruled out a fuel delivery problem. Im going to change the spark plugs now

I bought this 91 b2200 5spd carb a few months back and ever since it has sputtered worse and worse. When I give it gas or stop it stalls out sometimes. Well it stalled out on me while I was giving it gas, then it wouldn't start back up. I towed it home and changed the fuel pump (didn't need it) I changed the distributor cap and rotor and coil. I got it started with a little trouble then adjusted the idle screw and it was running fine until it started sputtering again and died on me at a stop light. couldn't get it started so I towed it home and now I don't know what the next step would be. HELP PLEASE

Keep in mind ive ruled out a fuel delivery problem. Im going to change the spark plugs now

Before you start throwing parts at it, do some diagnosis. Eliminate what is working first. Do you have spark down to the plugs? Are plugs wet or dry? Will it start with starting fluid? How's compression? Timing?

Well the old spark plugs were in really bad shape. I swapped them and cranked it and it started right up. Although it is still sputtering. Ive read various threads on the same problem with this truck and I saw something about a vacuum diaphragm in the carburetor? I don't know much about carbs