Bought a 70 XR-7 for my wife for christmas, have been trying to take care of the punch list of things that needed to be fixed. The Tach was not working, so I started to look things over, a previous owner had installed a Pertronix electronic ignition, coil, & distributor. instead of running the wire from the Tach (red w/ green stripe) to the positive side of the coil they buried it in the harness and ran a “new wire” to the coil. was easy enough to fix, just pulled that “new” wire off the “BATT” terminal and installed the one from the Tach…Viola! Tach is working, car runs fine. What Im trying to figure out is what did they splice into to get a hot from the switch to coil? they tapped into a wire in the main harness where it comes through the firewall, where the wiper motor splits off (and the oil pres, temp and tach break off too), was wanting to make sure they didn’t “sacrifice” something else to get the coil to work (seems to be their MO). see pic … pretty sure the heavy gauge wire which is kinda yellow with the big plug is possibly for the factory air (which is not in the car), is this other wire from the AC as well? it looks like a brown wire. Any ideas? Thanks
Darn…could figure out had to get the pic attached