Fun tach question

[Buck hour]

I have installed the painless wiring kit 10110 in my 77 7 and everything works better except the tach.. I know the purple wire goes to the negative on the coil. But the engine won't start when it's wired like that. When I move the wire to the positive post on the coil the tach works but the needle bounces when you use the turn signal. As funny looking as it is I'm not even sure how thats possible since they are on two completely separate pigs coming from the wire harness. I tried their tech support. But all they are able to do is read diagrams. Trouble shooting seems not to be their strong suit. Please help!

 

[jps4jeep]

wierd, not sure how the tach is being effected by a turn signal. what type of tach is it? factory or aftermarket? The issue might be with the tach, it could have a faulty ground inside or a short. honestly with out being there with a meter it's hard to diagnos.

 

[Buck hour]

wierd, not sure how the tach is being effected by a turn signal. what type of tach is it? factory or aftermarket? The issue might be with the tach, it could have a faulty ground inside or a short. honestly with out being there with a meter it's hard to diagnos.

It's factory and strangely enough it's also magnetic..

 

[frhrwa]

how many wires and what colors..? 6 or 8cyl..

 

[josh94yj]

LOL so much for PAINLESS huh??? some kits require certain parts to be upgraded, make sure that your kit does not require you to update your tach pick up or your tach

 

[Buck hour]

how many wires and what colors..? 6 or 8cyl..

Is a 4.2 and from memory I have blk/red/orange-wht/and orange. Blk to ground,red to the coil(+ post) /orange for light and orange-wht to power(tapped into the gas gauge).