- Sep 18, 2009
1980 Pontiac, full gauges and tach, electric choke, delay wipers, power windows, no AC, no radio, wiring "looks" intact. But when you turn on the running lights, the dash turn signal indicators glow, the tach jumps 1000 rpm, and the gauges sway. If you turn the dash lights dimmer off, it doesn't happen. I know what you're thinking-BUT. Turn on the wipers and the same thing happens and if you push the washer it gets way worse. Then wipers only work if you futz with the switch, and if they feel like it, they work great, sometimes. But if you don't use any lights or the wipers, all gauges, tach, directionals, stop lights, emergency flashers, everything works. All the external lights work but then that causes the issue. The grounds look good and I can't find any smooshed or pinched harnesses. All fuses were wrong values, missing, or blown. I set them straight. Short of changing the entire harness- what could this be????