P0136 Code and O2 Sensor 2 Bank 1 voltage

[2000StreetRod]

abnormal reading

The voltage output range of an O2 sensor is typically from 0.07 volts to 0.93 volts. A constant output of 1.28 volts indicates a lambda of maybe 0.85 or an air/fuel ratio of 12.5 (extremely rich). This reading is beyond the range of a normal O2 sensor and is only available from a wideband O2 sensor. The voltage value (if valid) is probably the limit that can be read by the PCM. I suspect either the sensor element has totally failed or there is a problem with the wires connecting it in the circuit.

 

[patricktolo]

Where is/are Oxygen sensors Bank 2 located on a 2000 Ford explorer xlt OHV 6 CYL?

 

[TheTrap]

P0136 Code and O2 Sensor 2 Bank 1 voltage (with Chart)

Advice is what you ask for when you know the answer but wish you didn't. So...I ask....

I got a Code PO136 today on my 2000 Explorer V6 SOHC, 180K, which my Actron CP9580 points out to be the Oxygen Sensor 2 Bank 1 (O2S12)[code corrected] . I cleared the code and will be monitoring for recurrence as I continue driving the Ex. From what I've read here it could be several things like the O2 itself, wiring, the catalytic, or dirty connections.

I ran a stationary Driving Monitor Test and looked at the O2 sensor voltage readings for 25 frames (64 seconds) while changing gears from Parking to Drive and back to Parking. The voltage rading were as follows:


Bank 1:
Sensor 1 (O2S11): .040 - .760
Sensor 2 (O2S12): .000 - .210 ---> Suspect per OBD2 Scanner(?)

Bank 2:
Sensor 1 (O2S21): .040 - .740
Sensor 2 (O2S22): 1.275 - 1.275

[codes corrected]

Since there is a lot of talk that sensors are seldom the culprit I am curious as to what is the normal voltage range is for these oxygen sensors. Can you tell by the readouts if a sensor is faulty?

Sometime this weekend if I get the chance I will get under the hood and inspect the wiring and do a little spring cleaning before I start replacing parts or doing a more detailed troubleshooting and checking for leaks, or start sweating about the notion of thinking of the catalytic.

Few notes about the Ex:

The Idle on the Ex is not as smooth as I think it could be but it is not bothersome or problematic. I am sure I have a very small coolant leak somewhere that I have not been able to find. I know because at one point the Ex was making a lot of 'hamster' noise in the console area (heater core/lines(?)) and was overheating. After I replaced the thermostat I realized that there was a good amount of coolant missing in the radiator. The reservoir was full.

Any ideas?

.

Have you tried the procedure to let the computer relearn the idle? Your supposed to do it anytime the battery has been unhooked

 

[AeroRamer]

This was a long time ago. So, yeah, plenty of time has passed. I am not worried about this at this point. I still have the Ex but it is not my daily driver. It is now my weekend or errands car. Not in the best shape but I still have her!