I had a similar problem on an 85 2.8 BII, it turned out to be a worn out ignition switch. The motor would start right up, but as soon as you 'unturned' the key back to 'Run', the motor would die.
When you turn the key, it moves the internals on the ignition switch so they contact the corrcet wires. The copper in my switch was worn out/dirty so when in 'Run' it wasn't making good contact with the wires, making it only work if you had the key in the perfect spot. I would take it out and see how it looks.
I beleive it is on top of the steering column under the dash(not sure on the old ones)
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I have a major issue I can not figure out. My sons 84 Bronco ll 2.8 Liter will only runwhile ignition is in the start ie Starter ingaged position. I can not find any broken wires anywhere. Fuse box fuses are OK and have been changed. Is there a fusible link somewhere? Where can I look for the problem?
