Test Conditions:
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.
Codes EO21, EO22, EO26 and EO27 clear. Transmission in REVERSE or DRIVE and brake switch closed (not braking). ISC throttle switch open. Throttle angle greater than 17 degrees. Engine speed greater is at least 1400 RPM.