Rusty if these units were made with the shielding in there wiring looms like the factory cars running and ecu with shielding or where you can mount it inside like their cousins can . You wouldn’t have half the issues people are experiencing.
It is not just the shielding. You can buy "plug and play" units like Holley HP/ Dominator/ etc for some applications (I think hemi, now too) but you still have to lay the harness in and route it so certain OTHER wiring in the car doesn't screw with it
One good example I always mention is MSD. "Let's say" you have a bone stock Mopar with a solid state voltage regulator, and you install MSD. The MSD can screw with the VR and drive the charge voltage nuts. Also the MSD distributor trigger CAN BE FALSELY TRIGGERED by it's OWN SPARK output from the plug wires!@!@
So right there is a simple situation that can drive some guys nuts. Now multiply that with your O2, your throttle sensore, etc etc, and "Houston, we have a problem"
