Wiring Harness for 1996 Plymouth Neon

Changing out the harness is a good idea but without understanding what is causing the problem, it might be the same with $ wasted.

Somewhere something is loose causing intermittent continuity etc. I would suggest rechecking the repairs of the wires, check all connectors (unplug and check for contaminations) and ground circuit.

Lets restart from the basics.

https://www.2carpros.com/articles/car-cranks-but-wont-start

We need a starting point. Go through the above link and find out what is missing causing the non starting. From there we would work through the system that requires attention.

You're welcome.

How is the going? Have you found the problem?

What is missing causing the non starting?

I sent you a link, go through it and test the various steps to determine what is missing. You need to start somewhere.

https://www.2carpros.com/articles/car-cranks-but-wont-start

Here is the link again.