Tachometer gauge issue

[Burning$]

No reading on the tach (RPM) gauge. First I checked the gauge to see if it was getting power. No issue there. Did some searching online seen some post that suggested checking the “gray” wire at the distributor that goes to the gauge. Well I’m not seeing any “gray” wire going to the distributor. I do have a gray wire that’s not connect at the other end to something in the photo attached.
Anyways any thoughts on what to check?

 

[badrano]

You could do a continuity check between gray gauge wire and the disconnected end at the engine to see if it is the same wire.

Where the tach signal comes from depends on the type of engine you have. Which engine do you have?

 

[nola mike]

As always, if you don't tell us what you're working on, I'll assume it's my engine. In which case the gray tach wire should be attached to the coil neg, not the distributor.

 

[Burning$]

mercruiser 3.0