cheers that should definately help, hopefully this will help a few others out to.

just had a thought would wire comming from ecu to the power transistor be putting out the signal needed? it would only be a single wire then and would be easier to get to.

No, have a look at the diagram - theres 4 wires from the ECU, 1 for each coil.

There's 4 power transistors inside the Power Module.

Each one is separate so that there's minimum interference between each circuit.

of course cool alright well ill give it a shot over the weekend and let everyone know if it works

I just read it was an aftermarket. I agree with the approach of using the power transistors to get a single signal.

When wired wrong, I've heard of the SR20/CA18 factory ECU tacho driver burning out.

Going to the source is a good idea.

Okay so i have been very lazy but i finally fixed the tacho. i followed TnPshow's diagram at it worked perfect. I cut into wires at the power transistor unit using the four outgoing wires as it was easier to get to. as for diodes i just used the biggest ones Dick Smiths had. better to be safe than sorry. hoepfully this helps a few people out. cheers