Notes On Intermittents
WARNING: This page is about a different car, the 1988 Cadillac Seville and 1988 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.
Check for binding throttle linkage due to throttle valve, cruise control or throttle cables, TPS installed improperly, or throttle shaft binding. Check for proper throttle return spring and throttle return spring installation.
Probe ECM pin "C10" to ground with a voltmeter. Manipulate wiring and connectors at closed throttle and watch for 5 volts, indicating an open from pin "C10" to ground. Manipulate wiring and connectors at open throttle and watch for zero volts, indicating short to ground on circuit No. 427.