87 ETA no spark

[tH16]

Cross-posting because I've had no response in general technical.

So I still have no spark from the coil. I have a constant 12 on the positive AND the negative. No pulse on the negative. The reference sensor has been replaced but the speed sensor has not, but swapping the two does nothing.

I've read Jlevie's no start response over and over, and I have gone through and traced out diagrams in the Electrical Troubleshooting Manual. I have replaced the ECU, and the coil. Main relay is good. I have fuel.

Any other ideas? Something I'm missing?

[tH16]

Update, as far as I can tell the fused link in the rear is good, and my grounding straps are good.

[paperplane94]

CPS or ECU
or dizzy and rotor problem
or signal wire problem from ECU.

[B-well]

On board computer relay box

looks like this



located on the interior drivers side firewall up pretty high

if your DME is not humming aka firing the coil this is the culprit