tach problem

[mustang112119]

i have a question when you turn my key on my tach shoots up to like 4 grand even when its not crunk when it is it wont ever come down below 4 but it will go up past it its done this for a while but its never really bothered me any suggestions its a 92 mustang nonturbo maybe its the tach signal wire maybe its grounding out or somethan which wire is the tach signal wire thanks

 

[Stinger]

Sounds like the typical ignition module "partial" failure...

 

[Asha'man]

It might be related to the ignition module, but your tach is probably busted. Mine did the same thing, even after I did the turbo swap (no more DIS module). Swapped in another stock tach and it works great now.

Brian