Earth/Ground Issues
Symptoms
Dim or flickering lights, erratic gauge readings, intermittent electrical faults that come and go. The engine may misfire or run poorly.
Cause
The Z-car uses a single-wire electrical system with the body as the return path (earth). Over 50 years, every earth point corrodes, increasing resistance and causing voltage drop. This affects everything from the headlights to the ignition system.
Fix
Clean every earth point on the car.
There are approximately 15-20 earth points, on the engine block, body, dashboard, and rear.
Sand the contact area back to bare metal, apply dielectric grease, and retighten.
Adding supplementary earth straps (engine to firewall, body to battery) is cheap and effective insurance.
Cost: virtually free.
Time: 2-3 hours.
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