cranks but won't start

Unable to access actual injectors without removing intake. However, we were able to probe injector lead with test light. When car won't start, there is no injector pulse. When we spray ether into throttle body, engine fires and injector pulse is present.

An incandescent test light is not a good way to check for pulse. First off, your looking for a ground signal, not a power signals and the but can damage the quad drivers in the PCM. Once you get a little better feel for exactly what is dropping out whether it be power supply or ground pulse and for how long, you can pursue a more specific path. We have probably gone as far as we can in this venue because it's going to take some in depth diagnostics.

When we used the test light we first connected to ground on battery and confirmed continuous current on the positive input to injector. When we switched the connector to postive side of battery and tested the ground side of injector there was no pulse in no fire mode until ether was added. Once engine fired, there was pulse on ground side of injector.

It might be time to start taking a closer look at the cam sensor and related circuits.