Mustang Restoration Groundwire
Jim Smart
January 18, 2016

This happens more times than we’d ever admit to you, our treasured readers. You flip a switch or twist the key and the darned thing doesn’t work. You crank the engine, pump the gas, and it won’t start. Pull the headlight switch knob and there’s a brown glow in the lamps. The turn signal blinks slowly or too rapidly. Parking light operation is hit and miss—mostly miss. Stereo pops in and out.

Are you beginning to see a pattern here? Most electrical system gremlins are rooted in poor grounding and bad connections. When electrical problems are intermittent and hard to find it is likely a poor ground. Just because something looks grounded doesn’t mean it is ground. Disconnect the ground and make sure you have solid metal-to-metal contact. If there’s paint in between the connector and body you don’t have a solid ground. Use a star washer in between the connector and body and be positive you have continuity.

We are always astonished at how many Mustangs we see without a ground strap between engine and body. Engines sit on rubber mounts and are insulated from grounding hence the reason for a ground strap. And one other thing—when you install a Pertronix Ignitor electronic ignition retrofit kit, don’t forget to reinstall the ground lead that was used with your ignition points. The breaker plate still has to grounded or you could face a no-start condition.

How long before AAA gets here?