Just picked up a 1989 F-350 c/w 5.8 engine. Service body(old electricians truck) The night i bought it, it was idling at about 3500 rpm, so when i got it away from the previous owners house, i stopped and unplugged the IAC. Settled it right down and it ran fine after that. Until a few days back where it just died on the road. Felt just like running out of gas. Waited a few mins after winding it over feverously and it finally started again. I did have to plug the IAC back in, but i really feels this didn't cause the truck to restart. Anyway.. it was fine for the rest of that day, now it has done it again today. Twice. Just dies and leaves me stranded for a few minutes. The fuel pump seems to be pressuring up..i can hear it when the key is turned on. This is a single tank unit i believe, but it has got the switching canister under the driver's door on the frame rail. Maybe one tank was removed when the service body went on it?? Anyway....where shoudl i start. I've read a million posts here and there and I am thinking of trying the ignition mod and the IAC for now....am i on the right track? Truck runs fine when its running... As far as the IAC goes.. it is wise or otherwise to be running around with it unplugged although it runs great with it unplugged? I don't want to install it only to find out that its not the problem.. non-returnable of course. Any help ASAP is greatly appreciated. Its great to be able to come here and learn!! Thanks fellas! Chad I wont be far if anyone needs more info to 'properly' diagnose me on here!! haha

 

Have you tried pulling error codes?