My truck has blown the PCM 30 amp fuse under the hood 2x's this past month.I have had the truck for over 5 years now and this has never happened before.Both times it happened, I shut the truck off and walked into a store, came out and turned the key and it crank and it will fire like 2-3 cylinders, then it pops the fuse.I was at the autoparts store the last time it did it and I put 3 - 30amp fuses in and tired to start it right in a row and it pop'd all 3.Went in and got a 40amp fuse, put it in and it was fine so I drove it home.Anyone have an idea what it could be?Never blows while idling or driving, only after shutting it off and trying to restart it.

 

You might check the PCM chassis ground. If it is loose or dirty, it could be causing voltage spikes.

 

Do you know where this ground is located at?

 

It's usually grounded to the body near the neg battery terminal on most Fords. I haven't looked at mine to see where it actually is.