Installting a Tachometer on a 1990 D-150

How hard would it be to install a Tachometer on a 1990 Dodge D-150 with a 5.2l V8? What would it entail?

You would need to hook up a power lead, a ground lead, a switched power lead (only on when the ignition is on), and a trigger wire. The trigger wire can be hooked to the negative side of the ignition coil.

Let me make sure I am understanding this. The tachometer that you buy at the store will have the follow set of wires coming out of the back:

+ Power Lead
- Power Lead
+ Switched Lead
Trigger Wire

Which is connected directly to the negative terminal on the coil.

Am I missing anything?

Let me make sure I am understanding this. The tachometer that you buy at the store will have the follow set of wires coming out of the back:

+ Power Lead
- Power Lead
+ Switched Lead
Trigger Wire

Which is connected directly to the negative terminal on the coil.

Am I missing anything?


That about covers it. Some tach's may combine the positive lead and the switched lead into 1 wire. Good luck and let us know how it goes.