I have a 95 F350 with a 5.8. I noticed that the previous owner had put an ecu from a 94 F150 equipped with a 302 in it. Also had replaced the pip with one from the same truck. I bought the correct one from a salvage yard and the truck wouldn't start. I then got one from local parts store... Still no start?
How is it that the incorrect one works(or at least starts and is somewhat drive able)and the correct one won't?

 

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