Note On Intermittents
With engine running, manipulate O2 sensor harness, PCM wiring and connectors while observing PCM parameter ED33. If fault is induced, ED33 will jump to less than .37 volt and ECON status light will go off. Manipulate ground to engine circuit No. 413, and look for a loose ground eyelet or ground eyelet installed at wrong location. If lean engine operation is suspected, perform PFI SELF-DIAGNOSTIC SYSTEM CHECK . If O2 sensor circuit appears to be okay, go to PFI CHART A-6, OXYGEN (O2) SENSOR TEST .