Here's the problem: My dad's 1990 4.9 E4OD won't start. I can start it by jumping the relay though, fires right up. Thought Neutral Safety Switch, cause run the shifter an few times an would start. Well replaced it but to no aveil. The rod in the steering colum has already been replaced last year, without jumping the relay nothing what so ever happens when turning the key. Battery I know is good, and once fired up shifts normally, well normally for a 200k mile truck.

 

Take the small wire off the relay and make sure you are getting 12V there when someone turns the key to start.

 

If not?

 

Bad ignition switch, or something in the wiring from the switch to the relay. I would guess the switch.

 

Thanks man, it starts now.
Appers to have been both the Neutral Safety Switch and the Ingition Switch. Now time to start trying to fix the tilt steering.