1989 Ford E-Series Van Engin spits and sputters Idle issue

Engine Performance problem
1989 Ford E-Series Van Two Wheel Drive Automatic 145K miles

I have a 1989 Ford E150 w/ a 302ci - 5.0 liter v8 3/spd-OD trans. 145,000 miles (45K miles since engine rebuild)
Over the last couple months, my engine will sputter periodically while driving and sometimes will stall in traffic when I stop. I restart the engine and drive away ok but sputter continues. It's most noticable at speeds at or below 45 mph. I also smell unburnt gas fumes and fuel mileage may be suffering too.

The engine light comes on until engine warms then goes out.

Also, sometimes when I come to a stop, my engine is still racing at high idle. When I hit the gas - as if to get the idle to come down - the engine races higher instead and have to hold the brake pedal hard. So, when I turn off engine and then restart, the idle is normal again.

Any ideas? Any recommendations? Thanks in advance.