Jeff...For what it's worth, I had similar problems(we tried every fix we could think of) which I traced back to that wonderful Rochester 1bbl...it would load up under similar circumstances to yours..hence, the sputtering, coughing and gas smell. We ultimately determined we had too much fuel pressure...went to NAPA bought an inexpensive in-line adjustable fuel pressure regulator and dialed it down to about 4 to 4.5 lbs and the truck ran like a charm.
