Connecting stand alone ECU to Tachometer
 

Hi all,

I'm trying to connect my ecu to the tach. I forgot to label the wire when I took it appart. Can anyone point me in the right direction? Is it on connector X-17 or X-25? I can't find it in the wiring diagrams.

And I did search first. Looks like there are multiple ways that people have tried. Y/Blue wire over by the ECU seems to be most common. A lot of these connectors are gone on my car though, does anyone know the Common Connector name of the yellow connector that has this wire in it?

Are you trying to get a crank position sensor signal? What exactly is this for?

Actual engine speed and rotor position is calculated based on the Ne and G sensors. Both those signals are needed if you were planning on sequential injection. I'm not sure what ECU you are using, but if you don't have a pretty good handle on how crank position is resolved and how ignition systems work you'll get really bogged down in figure it out.

Page Z-30 of the factory wiring diagram shows the tacho signal comes from pin 2B on the ECU and the wire is Yellow/Blue as you've said. The signal jumps over to page Z-42, where it passes through common connector X-15 before connecting to the dash cluster, shown on page Z-121. Careful, there appear to be two Yellow/Blue wires in connector X-15.

Awesome. Thank you.

Arghx, I'm running an electromotive TEC Gt. it has a tach output wire, it was hooked up before I attempted the big re-wire, but I must have not labeled where it connected to and couldn't find where to hook it back up.

I'll go look at x15 and see if I can find the remains of the old tack out wire.

Thanks again

Ah, so you really did just want to hook up the tach. Sometimes people don't even know what question to ask.

the screws that hold the tach into the cluster could be used. the top screw is ground, left screw is switched 12v, and right screw is tach signal.

But that is a very fragile connection

You can also pull RPM from Data Link Connector "IG" terminal or X-07 on passager side under dash

Where do i get tacho feed for rev counter? My car is running link g3. My factory rev counter doesnt work at all, would like to fix it and or hook up another rev counter. Is it possible to get feed from ecu, one of the for coils, or igniter? Thanks

kevin_syko, the OEM ECU sends a pulsed signal to drive the tachometer. If the Link G3 has a tacho output pin, connect it to the wire that goes to pin 2B on the stock ECU connector.