i got a 93 ranger 2wd 5spd with a 2.3L 4 cylinder. when i start the truck up, i can shut it off just a minute later, and it won't start. i go out a couple hours later and i start it up. as soon as i turn it off, it won't start. the cat was clogged so i cut it off, which helped alittle, but it still does it. the truck did sit for a number of years and i have had to replace numerous parts including..timing belt, spark plugs, alternator, battery, solenoid, water pump, etc. after it is off and i try to start it back up, the engine does turn....it just doesn't want to start back up unless i let it sit for an hour or two. any ideas as to what it may be?