2000 Intrigue Starting Issues
 

2000 Oldsmobile Intrigue 3.5L, 200k miles
Normally runs fairly well, plugs and air filter replaced in the last 10k miles, FPR replaced about a year ago. Ignition system seems to work fine (will fire off on starting fluid).
We tried injector noid lights and got just a quick flash, then nothing on subsequent cranking. There is constant battery voltage to one side of the injectors on both banks of cylinders.
We connected a Genesis Evo scantool and viewed a custom data stream during cranking events. Before cranking injector ms was usually listed at about 55 ms. The first cranking would occasionally try to catch, but injector ms was quickly reduced to 0, and could only be brought back by cycling the ignition key. Usually the injector ms value jumped straight to 0, but once we caught it at an intermediate value (28 ms), only to have it drop to 0 during the next cranking attempt. VTD Fuel Interrupt (which we suspected) remained listed as inactive throughout our tests, seeming to indicate no problems with the Passlock VTD system. We don’t have a flashing antitheft light, and from my understanding after an unsuccessful Passlock attempt the fuel system is disabled for a moderate period of time, while the injector ms in our car will reset to ~55 nearly immediately. The fuel pump primes at first key on, and turns on after a little cranking and is listed in the datastream as cycling on and off as expected.
We also graphed RPM calculated by several sources: CMP, 24X Crank, and general Engine RPM. All displayed readings, although not identical ones. My understanding is that this is non-wasted spark engine, so in order to get any spark the cam position sensor must be operating.
Is the injector ms change described how a VTD event is controlled? Could the drop from 55 to 0, despite VTD Fuel Interrupt being listed as inactive, indicate a problem with the key cylinder sensor? Some sources recommend doing the key relearn procedure, even if no new key or cylinder has been used. We may try that next barring any other suggestions.

Thanks for any insight you can give us.
Mark