yo J
How are you doing?
ok, here is what I have on it;
Testing, Bronco & Ford - three wire O2 sensors; two gray wires and one black. The black should read ground. One gray wire should read 12V with the ignition on, and the other gray wire is the one we are after. Probe this wire with the engine warm, and running with a voltmeter’s (+) probe, and ground the negative probe. While the vehicle is running, the reading should be approximately 0.5V. A reading below this indicates a lean air fuel mixture; a reading above this indicates a rich mixture. If no reading is present, and all connections are good, the sensor is probably in need of replacement
Source: by broncoii.org
http://www.broncoii.org/techpages/eeciv/index.htm#Oxygen
the gray wires may llok white..or gray...lol - this is a common problem with some tech resources that seem to stray from the actual wire color coding by Ford;
Signal; "The signal refers to the voltage relayed to the ECU (Electronic Control Unit) from the oxygen sensor. Different kinds of sensors relay different signals. A titania style sensor does not generate its own signal or voltage, it receives 5 volt from the ECU and sends back a signal from 1000 ohms resistance (on a rich mixture) to 20,000 ohms resistance, (on a lean mixture) depending on the current air fuel mix. zirconia sensor generates its own signal (voltage) and will deliver 0.45 volts when the air fuel ratio is stoichiometric. If the air/fuel ratio is lean (say 18 to 1) the sensor will deliver less than .045 volts (as low as 0.0 volts for straight air) and the ECU will allow more fuel through the fuel injector. If the air fuel ratio is rich (say 12 to 1), the sensor will deliver more than .045 volts (up to 1.1 volts) and the ECU will decrease the fuel through the fuel injectors.Newer model cars are now coming with Air/Fuel sensors and Wide Band Oxygen Sensors. A Planar air fuel sensor operates like a zirconia sensor and generates its own signal, while the wide band oxygen sensor is similar to a titania style in that it is dependent on a controller or ECU to generate a signal. The speed at which the sensor can switch between reporting a rich to lean (or lean to rich) signal back to the ECU is called the cross count. The higher the quality of the sensor, the higher or faster the cross count...".. Click on the word signal in the narrative
Source: by sparkplugs.com
http://www.sparkplugs.com/sparkplug411.asp?kw=2+Wire&mfid=0
Overview; "...Oxygen Sensor (O2) or (O2S) or (O2’s); These have been given many names, all identify the same item on the engine: • Oxygen Sensor (O2) or (O2S) or (O2’s) • Exhaust Gas Oxygen Sensor (EGO) • Heated Oxygen Sensor (HO2) • Heated Exhaust Gas Oxygen Sensor (HEGOS) Not all Oxygen sensors are heated, so using the word “heated” might not be correct for your vehicle application..."
Source: by Ryan M (Fireguy50) at
http://fordfuelinjection.com/index.php?p=31
READ A LOT HERE on why the voltage Varies in relation to RPM, etc.
Did you do a Self_tst for Codes yet?
In one of your other posts here I believe I gave you our PAL, BroncoJoe19 's Self Test Link
a Self Test by BroncoJoe19 do the KOEO = Key On Engine Off portion first & Remember to have engine @ Normal Operating Temperature before doing the KEY ON ENGINE RUNNING (KOER) portion
http://broncozone.com/topic/14269-code-reader/page__p__74587entry74587
My head is killing me since I'm working on a project and need to finish up today so i have to go now;
btw, Bosch makes both the OEM and aftermarket O2 sensor Advance Auto has em on Sale now.
Have you ever looked in my broncolinks.com Site:
see more O2 LINKs in there under EMISSION; -> Oxygen (O2) Sensor