well that's a problem.


all your tach outs from teh coils should be combined together, then going back to the dash gauge. try a signal 1K 1/4watt pull-up from 12v on that output to power the signal.

if that doesnt work, try the circuit you had before, remove the pull-up and use the spark triggers as the source, not the tach outs.

 

problem solved... thanks Braineack... i just soldierd all the tach outputs together and ran them to the rear of the cluster, soldiered a 1k pullup resistor to the back of a miata tach, soldiered wires to the (+), (sig), and (grd) tremainals of the back of the cluster, and modified both tach and cluster to install it in my festiva cluster. installed miata tach faceplate on top of the festiva gauge face. used tuner studio to confirm accurate operation.

 

And then proceded to RAPE FACE last night
This car seriously hauls *** and scares the **** out of me.
I thought we were going to die a couple times lolol

 

we only hit 130...man up...lol j/k