I bought this truck a little while ago from a guy who said it didn't run right.

The engine misses some during acceleration but really missed under light deceleration. I cleaned the carburator which slightly helped. I removed the catalytic converter(pipe rusty so it fell off) which did not help. I removed the EGR valve checked it with a vacuum and cleaned it, no help. I then removed the vacuum hose to the EGR valve and plugged the hose. Now the engine runs good.

Is there something that is suppose to turn the vacuum off on the EGR Valve during deceration?

Any suggestions are appreciated.