Note On Intermittents
WARNING: This page is about a different car, the 1990 Cadillac Seville and 1990 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.
Backprobe ECM terminal B9 with a voltmeter to ground. Lift both drive wheels off ground, start engine and allow it to idle in drive. Manipulate affected wiring and watch for sudden loss of voltage on ECM terminal B9.