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.
With engine running, manipulate oxygen sensor, ECM wiring and connectors while observing ECM parameter P.0.7. If fault is induced, P.0.7 will jump to less than .37 volt, and ECON status light will go off. Manipulate circuit No. 413 ground to engine, and look for a loose ground eyelet or ground eyelet installed at wrong location. If lean engine operation is suspected, perform DFI SYSTEM CHECK.