We have to recommend you ensure you're changing the correct oxygen sensor
first. Once you've verified you should then trace your Cadillac Eldorado's
oxygen sensor wiring from the computer to the sensor or vise-versa. You must
ensure that voltage (.5v) is present at the oxygen sensor output terminal
while your Cadillac's engine is running, and that the .5v is getting to the
engine control computer (ECC). The .5v is should actually be a rapidly
fluctuating .1 to .8 volts, but for simply testing purposes just look for an
average .5 volts and try to trace it back to the on-board computer. With the
proper diagrams you'd be able to trace the oxygen sensor wiring to the ECC
harness. There you can check for voltage and ensure that the oxygen sensor
signal is in fact getting to the ECC.
posted by SmogTips Support
