you dont use the ecm, you use one of the wires from the second injector, i think its blue
green wire on aftermarket tachs are the signal wire i belive
steal signal from the white wire w/ black sripe on the bottom plug of ecu.
to hook up the tach use the hot lead on the disributor and to any good ground wire and if there is a light hook it to the wire on you light switch
Hook up the red wire to the fuse box or another wire that gives power when the key is on. Hook up the white wire to a wire coming out of the headlight switch. This will make is so that when you turn your headlights on, the light will come on on the tach. If you don't mind the light on the tach being on all the time then just hook it to another power wire. Hook the black wire to a ground like a screw or a bolt. The green wire is the signal wire. Run it through your fire wall. Hook it up to the negative side of the coil. There will be a negative sign on the coil denoting the correct side.
tach signal wire is a blue wire with a black cap that ends on the top of the strut tower near the firewall...done
You would hook to the negative side of the coil. Some HEI distributor caps are marked "tach".
there is a white almost tanish looking solid color wire on the group of wires that plug into the guage cluster use a quick connect to connect the signal wire from the tach to the white wire on the guage cluster
Tach signal wire is located at the PCM near the connector. Use the manual should there be need for help in locating it.
hook your green wire from the tach to the white wire from the coil PAC it should be a white and a yellow wire coming from the coil. the tach should have a white wire that will be your light inside the tach a red wire for power and a black for ground.. good luck
Hook it to the negative side of the coil.
DISCLAIMER: I am not responsible for your actions You need an ECU diagram of your vehicle. Find the correct pin # and find the wire that attaches to it. Use a wire tap and run that wire as the signal wire to your new tach
Since the coil is in the distributor, simply hook the tach 'trigger' wire to the out put on the side of the distributor cap marked 'tach'.