Note on Intermittents
WARNING: This page is about a different car, the 1990 Cadillac Fleetwood and 1990 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
Enter diagnostics. Manipulate ISC wiring while observing OFF throttle switch status light and ISC operation during ECM output cycling. Manipulate TPS wiring and connector while observing ECM parameter P.0.1 for jumps, skips and intermittent behavior.
Check for TPS secured to throttle body (both Torx screws tight). Cycle TPS through its full travel while observing P.0.1. Check for proper part number TPS installed on vehicle. Remove and replace the TPS, ISC and ECM connectors and ensure they are latched. If all circuits check okay, substitute a known good TPS sensor and retest.