I am trying to figure out why my tach does not work. From searching I have seen that the green wire from my - term on the coil goes to the tachometer. The tach also has a black (ground) and red/black (12v) wire on the back of it (along with light bulb wires).

I have tested for breakage in the green and black wires and they read fine with the ohm meter. Power reads 12v from the red/black wire and ground.

When the key is on, 12v, when the car is started and idling it drops down to about 6v-7v. When car is fast idled the voltage increases again up to 12v.

With this information, am I believe that my tach is toast? Is there anything else I can test that will give me my answer?

Thanks in advance for the help!

Jim

74 260z, bone stock, su carbs.....reentered zland finally!

I have a install guide for an eletronic distributor that might help if you want it pm me with email address