Originally Posted by Sixtysixdeuce
The pressure regulator is mechanical. I'd be looking at the o2 sensor wires. Hopefully you didn't tie the signal wire into a battery voltage wire and fry a VLSI chip in the the PCM. I don't think they're protected on that circuit.
I feel pretty confident about the wire splices, did the basics, disconnected the battery, match colors and stripes on the wires, checked them after splicing each one, checked them when all were done, got out from underneath, got back down and checked them again. These wires were grounding out severely with one another prior to the splice repair, and I really believe this to be the source of the problem.
The original issue:
Driving down the highway and the truck shut off just like someone turned off the key, no hesitations, no sputters, just dead. Well, was getting a code for the crankshaft position sensor, so this was replaced. No codes anymore and worked good for 3 days. Half a block from the house one evening, deader than a hammer like the key was turned off again. Cranked it over, a few times started running. Alternator was not charging. Replaced alternator.
After the alternator replacement it would no longer start. After a couple hours of swearing like a sailor and making my neighbors a bit miserable, I found the shorted wires down on the transmission power supply. Struck me as really odd, but ok. Found a salvage wire harness, cut the connection off and spliced in. Since this fix, the truck runs as before when the fuel pump relay is not plugged in.
My concern is with the new alternator, may the PCM did take an electrical hit. Now my lingo here is not perfect, but I would call the PCM the computer or brain box of the pickup correct?
When it is spitting and sputtering with the fuel relay in service. The exhaust is so lean my clothes start smelling like I have been at the drag strip all day.
I plan on testing the fuel pressure tomorrow morning.