I generally have been able to learn everything related to my Miata by reading, but something about wiring just does not click with my brain...

Hopefully understanding this correctly, but I have a custom COP ignition harness built by someone years ago. While eliminating the stock (95') wires that went to the coil pack, I noticed there is a chassis ground that intercepts the ground wire between the coil plug and the harness plug. This ground does not exist on the custom COP harness.

Is this just an extra OEM ground for safety where the harness is also grounded further down? If so, I assume the ignition system is now running off a single ground and it may be a good idea to add that oem one back in to reduce noise and potential weak spark? I was told the harness was PNP so it may have just been an overkill ground as well...

Again, idk anything about wiring, any ideas are appreciated haha

(OEM coil wiring with ground)


(custom COP wiring w/ no ground)