83 L28ET crank angle sensor troublshooting

[outrider]

EDIT: Solved. In case anyone stumbles on this, the Z distributor requires pull-up. This dawned on me when it finally clicked that every testing procedure I read through tells you test with it connected to the car (so the factory ECU can pull it up). EMU has an option for pullup in the trigger setup, simply turned that on and started seeing signals.

 

I'm in the final stages of wiring up my ECUMaster EMU to the L28 I'm building for my 260, and having trouble getting any ignition trigger input. I'm running an 83 turbo distributor with the DIY 12-1 trigger wheel. I had assumed I just had something wired wrong, and jumped right to testing the sensor directly as well as the wiring to the dizzy.

 

On the harness side, I have switched +12 on the red wire, confirmed with a multi-meter, 12.4xx between red and black. I've poured over schematics and 99.9% sure that's correct.

 

I've also connected 12v and ground directly to the distributor, then checked from both of the remaining pins to ground looking for a 5v signal pulse. I'm not seeing that, although I do see something, like maybe 1v on the secondary trigger when the slit passes through, and just a couple millivolts on primary. I figured at this point the CAS was bad (the epoxy was all melty looking and kind of leaking out too), so I ordered a replacement for a 300zx, as it was cheaper and from what I read better.

 

I got the replacement today and it's acting almost the same. Difference being now I only get a couple mv on the secondary trigger as well.

 

I think I've narrowed it down to three possibilities.

1. I've misunderstood the wiring diagrams, and I'm feeding power to the wrong pin, testing the wrong pin, etc.
2. Maybe I need to use a pull-up resistor? But I'm hesitant to put 5-12v on the signal lines and burn something up, until I either find a schematic of the internals of the cas, or someone comes to my rescue and confirms that the sensor is sinking current rather than sourcing it.
3. The new CAS I ordered is also junk. Unfortunately the best odds of me finding one in Grand Rapids, MI this weekend would be a junkyard, so I might be running out to the pick-a-part tomorrow and looking for a Z or pathfinder or something.

 

Anyone have any other ideas? Have I misunderstood how to test these? Thank you for any help!

Edited April 7, 2018 by outrider
Solved issue

[outrider]

Attached is output from my scope (10mv/div). I was turning it probably around 100 rpm with a cordless drill. Thought maybe this might help if anyone had any ideas.

 

Top is the primary, if it's stopped on a slit it goes to 0. You can see the 11 pulses only get down to ~4mv though, and the missing tooth is where it stays at 16mv. Secondary on bottom behaves the opposite, outputting a 20mv pulse at the slits, and rest around 0 the rest of the time.

 

It's like it's working, just not 'amplifying' the signal? I guess from my reading I had expected to see more like 5v on the pulses.