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.
Check for throttle shaft and throttle blades binding, weak or distorted throttle spring, cruise or TV cable binding, and/or improperly installed TPS. Intermittent Code E27 can be induced by resting foot on accelerator during key on/key off for 10-second cycle. Check for intermittent open on circuit No. 427 between ECM and ISC.