i recently purchased a 2007 e450 6.0 missing he pcm. I put an old one I had laying around in and it cranks over but does not start. I get no power to injectors or fuel pump. Is this a sign the pcm needs the vin flash to properly work?

 

I would have to say no to the pcm needing flashed. I also have a used one I found at a junkyard from an 06 that I installed just to see if it worked and it did. However I did have codes for abs and other modules because they weren’t matched to the pcm. Check to make sure the pcm fuse isn’t blown.