I have my 93 f150 I bought a tach last year and in 2 weeks after putting it in my battery died I havn't put it back in thinking it was the tach that caused it but I'm not sure but to be safe I want to put it in but where to a plug it into some people say distributor cap some say ignition switch.. i have no clue. anyone know?

 

how many wires are there on the tach? was there a wiring diagram with it when you bought it or was it second hand? in my experiance there are 4 wires, ground, power to ignition switch that only has power with the key in the run position, one that gets hooked up with your dash lights for illumination, and a wire that goes to the negitive side of the coil. as for running the battery dead i would say that the power wire was probably hooked up live all the time.

 

The Tan/Yellow wire at the coil is the one you want to hook it up too. Other than that switched power and ground.

 

I feel dumb for asking but I can't remember do you have a diagram or a picture of the location of the coil? I don't wanna have to try n find it in all the wiring diagrams in my haynes haha

 

There is a power to ignition (green) Power to tach (red) Illumination (White) and a Ground (Black)

 

if u look at ur coil theres a green wire with yellow strip the green from the tach goes to that i hook the ground to the body the red to a switched hot in the fuse pannel and white to your dash lights

 

All the wires needed for any tach can be found in the instrument cluster connectors. You don't have to go thru the firewall - that's already done. Just pull the cluster out, unplug it, find the wires, splice into them, start the engine, and make sure it works (the cluster doesn't have to be connected). If it does, shut the engine off & finish the installation.

Ground - Bk/Wh, Bk, Gy/R, Bk/Y (except 4.9L)
Power - R/Y,
Tach - Wh/Pk
Illumination - LB/R

But it's easier & looks MUCH better to just swap in a factory tach cluster. For a '93, you need one from a '92-93 F-series (gas) or Bronco. For more info, read these captions:

 

For sure Steve.

OP, take a fun look through a junkyard and get yer tach there. Not hard to take apart a cluster at all.

https://www.supermotors.net/registry/22140/75545

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