found some info but what wire?

[foster180]

i searched this and found indirect info. i have a 90 nissan 240 with a red top that uses coil packs (4). My tach doesn’t work for obvious reasons. I got an autometer tach. I wired it like this: white-dash lights, red-power, black-ground, and green-tach signal (from ecu). I know this doesn’t work for two reasons, 1 I read about it on here and on zilvia.net 2 I tried it. Now I also read on here that I need to wire it to the ignition. But that’s all any one knew. What I need to know is what wire? It is not the yellow/red from ecu, that doesn’t work.Thanks

[MikeMurphy]

bump

[quiksilvia]

bump? good info, way to help out.

ive always thought that u have to connect it to a wire that is in the engine bay, on the cas or something, but ive also heard the yellow/red thing as well