1995 Taco Intermittent no start and mystery headlights - Grounding wires?

I have been having on-and-off issues with my '95 Tacoma. I have joked for years that she fixes herself and this past month it left me sit at a redlight for the first time. Ended up having it towed and then she started right up once it got to the garage. After many days, we ended up with a new fuel pump (original) and found a cracked ignition coil (original). Did not replace the spark plugs yet and I swaped out the clutch safety switch that was also causing intermittent issues.
Forward a few weeks later after running great, and so much better gas milage, I made a quick trip to my moms and when I stopped and went back out it would crank but not start.
I have also had weird issues for years, where occasionally my headlights will turn off unexpectedly, then pop back on. Have had many parts, switches etc. replaced.
After everything, I was reading about weird things happening if there is a faulty ground connection somewhere and I have been suspecting some of the issues are electrical. I know nothing about wiring, but will learn it. Where would I find a diagram of the wires and what they do for my truck? Any suggestions on where to start?

 

Start by checking all your negative grounds wires, the one from the battery to the inner fender is one that usually breaks or the connection gets loose, there are a number of places and a number of ground wires to check,
Battery to fender,
Battery to engine block,
Fire wall to back of engine,
ECU ground wires on the intake,

Your battery cables etc.

 

I know this is kinda' thread revival, but did you get your problem fixed yet? I'm wondering because I'm having the same issue on my truck (95 2.7l). The issue started differently, though. My lowbeam headlights weren't working, so I finally figured out it was bad wiring connection. I tore the steering column apart and spliced in a new wire. Problem fixed except that the truck wouldn't startwhen I finished. I know the fuel pump isn't running which is why it won't start, but I don't know which wire is making problems. In the process of trying to wiggle wiring to get the fuel pump working, I wiggled something wrong and now I don't have any lights either. Worse than when I started! Did you find any good wiring diagrams for these systems. I have some, but they're not very detailed. thanks

 

My problem is not fixed yet. We ended up narrowing it down to the ECU, I could not find a used, or refurbished one for the manual transmission. A local garage sent it out to be rebuilt and I am still waiting on it.
ECU number 89661-04051
I also ordered a Tacoma service manual off of Ebay, 2 parts.
Below are a bunch of threads I looked through for clues. Hope some it helps.

95-96-tacoma-4x4-electrical-help-needed.481977
ECU Pinout and Wiring Comparisons 1995.5 - The WELLwell.com
all-ground-point-locations.727612
grounding-locations.724741
headlight-switch-or-headlight-relay-bad.673207

 

I had a weird issue YEARS ago with my 96 2.7 4wd where believe it or not the ECU ended up being the problem. It kept throwing a check engine light for emissions or something like that. I had a backup ecu and tossed it in the problem never came back and drove it for years. It is very possible the ECU is on its way out the door. Might be a 95-97 tacoma ECU issue idk. let us know what you find

 

Thanks for the threads. I hope the ECU fixes your problem.