Is my igniter sending a tach signal ?

[Ryan_V]

I'm trying to determine if my 1JZ igniter is sending a tach signal once the car is started.

I'm under the impression that the igniter sends a 12V square wave signal(digital) down the black igniter wire straight to the tach cluster.

Yesterday I started the car and I measured the voltage of the igniter wire, and I got 0.05V at idle.

Is this even a valid way to determine if the igniter is sending a signal without buying a new one?

 

[Piratetip]

Do you have a scope?

 

[supradaddy0803]

When I checked mine to make sure I was getting signal to the Tach it was the same but on a different wire. Mine was a red with blue stripes and the voltage would vary depending on where the throttle was. I soldered a splice into that one and my factory tach works like a champ.

 

[Ryan_V]

Do you have a scope?

I don't know how to use one, and I'm having a hard time finding any shop that will look at it for me.

When I checked mine to make sure I was getting signal to the Tach it was the same but on a different wire. Mine was a red with blue stripes and the voltage would vary depending on where the throttle was. I soldered a splice into that one and my factory tach works like a champ.

I wish I could find another wire that is sending a tach signal, I'd just splice it as well.

 

[aphxero]

you sure youre on the right one? IS it continuous to ig-on the diag box? Should be on the 4 wire plug from the igniter. Iirc that plug is igf to ecu, ig- to tach, power, and ground.

 

[Ryan_V]

Definitely looking at the correct wire. It is off the small connector at the igniter. We checked continuity from the igniter to the gauge cluster, and the wiring is good.

IGF is a pin on the ECU, and I believe it may be the mentioned blue with red stripe wire.

Maybe I'll splice into that wire and run it to the tach to see what happens.

I found a blurb in the OEM service manual that says the dealership can actually hooked something up to test and make sure the tach itself works. I may do that..

 

[Ryan_V]

Just as a followup since hardly anyones ever does.

I fixed the tach!

I cut the tach signal wire at the igniter and ran that to the cluster directly, checked continuity, started the car,nothing ...no tach.

I then swapped another GTE igniter, and bam, I got a tach.

We took my igniter apart and you can see that on the 4 pin tach signal/IGF siganl side there is something that puked up through the clear gel that protects the components.

Case closed..my igniter wasn't sending a tach signal after all.