ECM Wiring Diagram

[Cbm8296 at aol.com]

In a message dated 12/29/98 2:23:04 AM EST, pfenske at bcit.bc.ca writes:

>Howday
> 
> For the tach signal you want the white wire running off the coil in the
> engine compartment. This sometimes runs through the ecm plug
> but continues onto the dash tach if used. The white wire has nothing
>to do with the ecm
> 
> gl:peter

I'm confused by this.  If the white wire doesn't go to the ECM, where does it
go and what is it's purpose?  Can I still get it from inside the car somewhere
like I originally thought, or will I have to run that dreaded wire out to the
coil?