I bought a 1987 f250 about 2 weeks ago,nothing but problems since..It started out as a miss at idle so I started changing things to fix the miss.I have changed dist cap,rotor button,modgul,spark plugs and wires,checked vaccum lines,I have changed coolant sensor,throttle senor,map sensor,idle control sensor,changed computer,fuel filter,took throttle body off throughly cleaned and blew it out,I was going to change fuel pump but i can hear it come on for a few seconds and then shut off and it looks new .i have done a fuel pressure test holds 45 to 65 pds.have done a compression test all good..the miss went away but know when it sets overnight it cranks and cranks maybe 30 sec. before it starts once it starts it will start easy everytime the rest of the day.does anyone have any suggestions please.....