My 98 Expedition all of a sudden blew black smoke out the tailpipe on start died

I recently bought an awesome 98 Ford Expedition XLT 5.4. Truck ran like a top except for every once in awhile it would hesitate on slight incline
. On Sunday night My husband filled the resevoirs before I went to the lake with my friend. The truck hesitated on the slight incline on the freeway to the lake. Funny thing is that the hill to the lake itself is very steep and very windy and no hesitation at all, went up the hill like a charm, then a steep decline to the lake.
The truck set for two days while we relaxed, chatted and read books. When I started the truck it started normal but my friend yelled that black smoke was pouring out of my tailpipe! That never happened before, then going down the freeway I smelled what I thought was the car in front of me, ended up it was mine. Checked under the hood when I took my friend home, and nothing looked suspicious. On Thursday morning started up truck, same smoke only on start then vanished before I left the driveway.
Ran around all day and truck ran fine. Friday morning started right up, black smoke on start gone before I leave the driveway, down the cul de sac and as I was turning onto the street, the truck just stopped, dead. Yikes! I borrowed a Orm II tester and the code would not come up, all it would say is operator error. I was told that the spark plugs were sometimes at fault and since I didn't know the last time they were changed since I bought the car in April, I enlisted my husband to help me change all spark plugs, what a job, I look like someone beat me on my hands and arms and shed a little blood, and luckily none broke.I checked the air filter and it was really dirty so I installed another one and checked all fuses, and the #24 under the hood 30A had blown.I tried the OrmII fault tester for codes but it once again said operator error and would not give a code., Well, when we were done the big moment and the truck cranked but wouldnt turn over. I was disappointed, I checked #24 and it had blown again, these arent cheap fuses cuz they are maxi. Noticed the theft light flashing fast and in some code one and then six blinks. I found it was the PATS and had locked my key out and I did not have a second one.
Next day had truck towed to dealship so they could take care of the key problem, said they have to program the key, they did a diagnosic and visual check and called to tell me that I needed a whole new wiring harness put in. That the previous owner had the wiring in a different configuration than ford. The one time super deal of $2,595.I think not.I was upset to say the least. I told them to not do anything else to my truck, I would have it towed back home. I went to the dealship and talked to electrical tech who had been working on my truck.I had a million questions on why he came to the conclusion he did on repairs. I told him that I was going to see what I could do myself on the truck and he directed me some, I don't think his service manager appreciated that much. He did get DTC codes for me and they are P16000, 01, 02, that there is a short to ground on the PCM power relay and isolate short to engine side of main engine compartment loom and found loom incorrectly routed,
Other comments were fluid leaks and oil leaks. That it was blowing fuse #24 and it needed 19 electrical repairs to include wiring, anti lock breaks, air bags and computer monitor. Towed back home, looked for 2 days for broken or burneden wires
The tech told me it is basically in the wiring and it could be anywhere.