Ok, had this problem ever since I put the motor in, oh, two years ago. But it never really mattered until now. Truck starts fine cold. If it turn it off pump gas, refire, its fine. But if the truck has sat between 2.5 & 4hrs, when I start it, it will fire up, then bog down, sometimes choke down, and others just idle extreeeeeeeemely low, like so low, I dont know how it doesnt choke down. Just so happens, now, I get out of class exactly 3hrs after I get to school, so I have to deal w/ this everyday, and pushin the brake w/ my left foot & resting my foot on the gas is getting old fast in our crowded lot. What could be the problem? Call it an 87 TBI 454 for diagnosis.