Originally Posted by
4 l-bodies
I haven't specifically looked in depth at the NY'er wiring harness, but if it is wired similar to L-bodies, this could very well be your issue. Your problem is more than likely in the Z1 circuit, esp. since you've changed out the PM and Hall Effect without finding a permanent solution. This is a dark green with black tracer wire. I recently helped a friend over the phone diagnose his GLHT that also abruptly died much like yours. He quickly narrowed down the problem with me assisting him while on the phone, after doing a few continuity tests. He found his problem where the two wires from the Z1 circuit meet at the bulkhead connector as they pass through the firewall. In his case, the wires pulled away from the connector, no longer being locked in place. Other times, I have found this connector to be very loose, also causing intermittent problems. He was slightly electrically challenged, but found the issue and repaired it easily. Assisted another guy on TD with this same exact problem recently too. Here are a couple pics from our correspondence.
That green with black tracer wire circuit powers the fuel pump, injectors, and also provides power to the positive side of coil. They tie together from the left and right side of the car at this connection. That's why there are two wires in photo. Think of it as a splice. I would locate these wires and give a tug on them to see if their still connected to the bulkhead connector securely.
Hope this info helps,
Todd