Where can I get a tack signal

 

Which motor do you have/
.
Problem is today's engines use multiple coils or coil packs.
Sampling from one pack would be at the wrong frequency for Tach accuracy..
The way around this is to sample 'current' at the main coil feed which would be a represenitive square wave for all coils one at a time as they fire, just the same as the old single coil system.
An adapter would need to be installed so the voltage drop from the sampling does not get excessive causing misfires during EGR operation.
The factory Tach signal comes from the PCM and is a different wave shape and frequency vs RPM for the digital Tach making an aftermarket Tach useless for accuracy.
Good luck.

 

The engine is from a1997 Lincoln 4.6 double overhead cams. I am trying to help a young college student get it running. Thanks for your help.

 

I didn't think that the 1997 Lincoln Town Car 4.6L had the dual overhead cams. You sure its not a single overhead cam?

 

I had the wrong model it is a mark 8 Lincoln.Thanks 39pu

 

Those years have a different version of ignition than the 97 up trucks.
I most resembles the V6 system.
This is the progression of ignition systems to todays individual coil over plug system now in use.
The PCM and harness needs to be used but the same issue is still present for Tach use.
Good luck.

 

Thanks Bluegrass, I think he found a kit from someone that will pick up a signal usable for the tack. 39PU

 

Good deal.
Let us know how it works out.
Good luck.