My '91 F150 has over 300,000 and is on it's 2nd motor (5.0 V8) with 90,000 that came out of a rolled '88 Crown Vic. The truck has loped when cold since the motor was installed 10 years ago and now my grandson wants to drive it. Has no cats and only has Thrush mufflers. I just kept the accelerator pushed just a hair until it warmed up but recently it dies occasionally at idle, cold or warm. I replaced the computer 5 years ago out of a 1990 F150 because neither fuel pump would come on. Replaced the wires, rotor, cap, plugs, and ICV today. Runs much better and stronger but I still have to press on the pedal to get it to start. The CEL came on but went off before I could pull the code. Any ideas where I should go next? Thanks!