[cc82z-28]

I have an 82 Z-28 that has a 406, I am using a Summit all-in-one dizzy with a cannister style coil. I have a seperate shift light and a Petronix rev limiter and I am using the stock tach that is in the dash. Everything works but when I have the lights on and say the electric fans are running and I am at idle waiting to make and turn and put my turn signal on, the tach and shift light bounce and light with the turn signal, any ideas why? The car is charging fine, no problem there, if the headlights are not on it is not a problem, really weird I know and I have to wonder if I need a tach filter wired in some place, I can't find the stock one that was on the car and am not sure what or where to put one. Thanks for any input.

[cobalt327]

Originally Posted by cc82z-28

I have an 82 Z-28 that has a 406, I am using a Summit all-in-one dizzy with a cannister style coil. I have a seperate shift light and a Petronix rev limiter and I am using the stock tach that is in the dash. Everything works but when I have the lights on and say the electric fans are running and I am at idle waiting to make and turn and put my turn signal on, the tach and shift light bounce and light with the turn signal, any ideas why? The car is charging fine, no problem there, if the headlights are not on it is not a problem, really weird I know and I have to wonder if I need a tach filter wired in some place, I can't find the stock one that was on the car and am not sure what or where to put one. Thanks for any input.

This might be due to the circuit(s) the tach, ignition components, and shift light is using for power. You could try a different power source. Routing the power supply wires away from the flasher coil and/or any other wiring might help. Be sure the grounds are all good- connect to bare metal!

Possibly a radio frequency choke could take care of it. Maybe someone will have something more on this.