Seems like No Signal to PCM

Recently did some dirt dragging with my wannabe “drag truck” and while I was at the event the fuel shutoff solenoid went out in the Truck. No problem, turn the key over before starting, get out and pull the plunger up with my hand and it started right up. Noticed I had an issue with my tach bouncing around and reading inaccurately, but it didn’t seem to be an issue. Wrong. Went to make my pass and the truck hung 1-2 shift (which had never happened prior)
Now my issues include no tach at all, GEN dash light and the light on the overdrive button stays lit. Truck starts and idles like normal, have not tried to actually drive the truck to see if it shifts normally. I’ve replaced the engine speed sensor, both fuel relays bolted to the firewall above the engine, fuel shut off solenoid, ASD relay and a few other things I read on other threads and still have the issues. Anyone have any help or ideas? Sorry for the long winded post, tried to cover all the bases to get the best help.
 
PCM likely shot the schit, or you have an unseen electrical issue.
Try to see if a scan tool can pull codes.

Mark.
 
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Make sure the wire from the battery to the fuse box on the fender well is clean and tight.

I’m gonna go ahead and replace that wire because I’m sure it needs to be done and do it as a check. Going to try and borrow a PCM out of another 97 automatic truck and hook it up to see if it’s the issue. If it fixes it, looks like I’ll be getting a PCM
 
The Hold in/pull in circuit aren't PCM related from what I recall.

I would be checking grounds.

Sent from my XT1575 using Tapatalk
 
The Hold in/pull in circuit aren't PCM related from what I recall.

I would be checking grounds.

Sent from my XT1575 using Tapatalk

I’ve checked just about every ground connection I can think of. If anyone has any insight on wiring that is more prone to failing than others, it would be greatly appreciated.
 
I'm having a similar problem with my 94' since I swapped a p24v in it. Tach worked great before, now no tach and no charge. I'm guessing it wont charge because the PCM doesnt know the engine is running. I also replaced the ESS, still nothing. I'm getting a rpm signal to my PCS controller but not the dash. I think I'm going to get a self regulated alternator and aftermarket tach since the stock one doesnt go high enough anyways! Lol
 
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