Oxygen sensor replacement

When we detect a lean mixture code from our vehicles, our first reaction may be to replace the oxygen sensor. However, testing oxygen sensors before replacing them is a good idea. The best way to check the operation of the sensor is to run a simple test. And all you need is a voltmeter. A voltmeter is usually cheaper than car diagnostic tools and is available within 100 eurs. Here I will use an original Autel PowerScan PS100 for 56 eurs from EOBD2.FR.
How to check if your oxygen sensor is bad and needs to be replaced:
Step 1. Find the oxygen sensor sensing wire, connect Autel PS100 to the feedback wire and ground and then choose the mili volt operation.
Step 2. Turn on the ignition key to start the vehicle and run the engine at idle to warm it up. Watch data on PS100. The voltage should move slightly at whatever voltage the sensor is centered at.
Step 3. When you pull the oxygen sensor data stream up, the output voltage from the sensors should constantly bounce between high and low with the meter dropping and rising, as the engine is running in closed loop. The volt meter should stabilize at the original operating voltage when the engine returns to idle.
If your oxygen sensor does not show the above reactions, it is probably that it is bad.
Note: If the error code shows a malfunction exists with related components such as an engine misfire or other engine problems, please do not perform this test.

code P054 heated oxygen sensor bank 1 sensor 2 heater resistance. code P1000 obd2 moniter testing not complete.get this code when battery power disconnected to the PCM.to fix problem take vechicle to shop they can use a scanner to erase codes reset the PCM.

Peter. The dealer did diagnose the problem. They said the car needed all 3 oxygen sensors replaced. They were replaced and the car is now returning codes p0172 and p0175 which are the only 2 codes coming up when the check engine light came on. My question is if the dealer sold me the incorrect oxygen sensors could this cause the computer to incorrectly set the p0172 and p0175 rich fuel mixture codes. There are no other codes coming up. My plan at this point is to check and clean the MAF, check my fuel pressure, and also the TPS but I did not want to waste my time if it could possibly be that the new oxygen sensors where the problem. Any help would be appreciated.

These codes, po 138 bank 1 sensor 2 shorted to voltage and code po158 means bank 2 sensor two shorted to voltage. these are the two rear oxygen sensors in the exhaust system. there two up frt and two in the rear, check the wiring on the two rear sensors, make sure that the wiring is not cut or stuck between metal. if the wiring is good then replace both rear sensors, when you get them ask for the left and right after the cat sensors. or bk1 s2 and bk2s2. after replacing them reset the computer. go to an auto parts sotre or if you have a code reader you can do it. hope this helps good day.

SAE J2012 Revised DEC2007 lists Diagnostic Test Code (DTC) P0133 as "O2 Sensor Circuit Slow Response Bank 1 Sensor 1"

This code basically means that the upstream oxygen sensor on bank one of your engine is not responding as quickly as it should to changes in oxygen leavels in the exhaust.

The usual causes of this is an oxygen sensor that is just plain worn out (if it has a lot of miles on it) or an oxygen sensor that is contaminated by engine oil or antifreeze leaks causing these fluids to be burned in the exhaust (like bad piston rings, defective PCV valve, blown head gasket, etc.).

In any case, the oxygen sensor needs to be replaced. However it should be noted that if it is caused by contamination like that described above, replacing it will only result in a new oxygen sensor doing the same thing if the cause of the contamination is not repaired.

Removal & Installation

Raise and support the vehicle.
Support rear of the powertrain frame.
Remove four rear frame bolts.
Lower the frame no more than 73.2 mm (3 inches).
Disconnect the rear oxygen sensor electrical connector.
Remove the rear oxygen sensor from the rear exhaust manifold.

To install:

Install the rear oxygen sensor in the rear exhaust manifold. Tighten the rear heated oxygen sensor (HO2S) sensor to 41 Nm (30 ft. lbs.).
Connect the rear oxygen sensor connector.
Raise the frame.
Install the four rear frame bolts. Tighten the frame bolts to 100 Nm (74 ft. lbs.).
Lower the vehicle.


Heated Oxygen Sensor Bank 1 Sensor 1 (HO2S 1/1)

WARNING: Handle the oxygen sensors carefully in order to prevent damage to the component. Keep the electrical connector and the exhaust inlet end free of contaminants. Do not use cleaning solvents on the sensor. Do not drop or mishandle the sensor.

CAUTION: Remove oxygen sensors with the engine temperature above 48C (120F). Otherwise the oxygen sensors may be difficult to remove.

A special anti-seize compound is used on the oxygen sensor threads. New service sensors should already have the compound applied to the threads. Coat the threads of a reused sensor with anti-seize compound P/N 5613695 or equivalent.



Fig. Showing the location of the HO2S Bank 1 Sensor 1

Heated Oxygen Sensor Bank 1 Sensor 2 (HO2S 1/2)

CAUTION
Handle the oxygen sensors carefully in order to prevent damage to the component. Keep the electrical connector and the exhaust inlet end free of contaminants. Do not use cleaning solvents on the sensor. Do not drop or mishandle the sensor.

CAUTION: Remove oxygen sensors with the engine temperature above 48C (120F). Otherwise the oxygen sensors may be difficult to remove.

WARNING: A special anti-seize compound is used on the oxygen sensor threads. New service sensors should already have the compound applied to the threads. Coat the threads of a reused sensor with anti-seize compound P/N 5613695 or equivalent.



Fig. Showing the location of the HO2S Bank 1 Sensor 2

Raise and support the vehicle.
Remove the heat shield.
Disconnect the heated oxygen sensor electrical connector.
Remove the heated oxygen sensor.

To install:

Install the heated oxygen sensor. Tighten the heated oxygen sensor (HO2S) to 41 Nm (30 ft. lbs.).
Connect the heated oxygen sensor electrical connector. CAUTION
Ensure connectors are securely installed beneath harness heat shield to prevent damage.
Install the heat shield.
Lower the vehicle.


Heated Oxygen Sensor Bank 2 Sensor 1 (HO2S 2/1)

CAUTION: Handle the oxygen sensors carefully in order to prevent damage to the component. Keep the electrical connector and the exhaust inlet end free of contaminants. Do not use cleaning solvents on the sensor. Do not drop or mishandle the sensor.

CAUTION: Remove oxygen sensors with the engine temperature above 48C (120F). Otherwise the oxygen sensors may be difficult to remove.

WARNING: A special anti-seize compound is used on the oxygen sensor threads. New service sensors should already have the compound applied to the threads. Coat the threads of a reused sensor with anti-seize compound P/N 5613695 or equivalent.

Raise and support the vehicle.
Remove the air deflector.
Disconnect the front oxygen sensor electrical connector.
Remove the front oxygen sensor from the front exhaust manifold.



Fig. Showing the location of the HO2S Bank 2 Sensor 1

To install:
Install the front oxygen sensor in the front exhaust manifold. Tighten the front HO2S sensor to 41 Nm (30 ft. lbs.).
Connect the front oxygen sensor electrical connector.
Install the air deflector.
Lower the vehicle.

Hope this helps; also keep in mind that your feedback is important and I'll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using Fixya, and have a nice day.

P0044 - HO2S Heater Control Circuit High (Bank 1 Sensor 3)

The P0044 is set when the ECM detects an excessively high voltage through the heated oxygen sensor heater circuit

Oxygen Sensors (O2S) or Heated Oxygen Sensors (HO2S) need to reach a minimum operating temperature of 750 degrees F to produce an accurate voltage signal. The faster the heated oxygen sensor reaches that temperature the faster the sensor will start sending an accurate signal to the Engine Control Module (ECM).

In order to achieve the require temperature, a heater element is included inside the heated oxygen sensor. The ECM controls the heated oxygen sensor heater element based on signals from the engine coolant temperature and engine load. The ECM controls the heater element circuit by allowing current flow to ground.

Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)

Possible causes
- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 3 circuit open shorted to ground
- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 3 circuit poor electrical connection
- Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 3 circuit
- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 3 circuit fuse
- Faulty Engine Control Module (ECM)

The ECM monitors the voltage signal received through the heater element circuit and determines the state of the circuit by comparing the voltage detected with the factory specifications.



Hope helps (remember to rate this answer).

your o2 sensor is bad. vsc will go on for any small DTC displayed on the MIL (cel)

P0037 LEXUS P0037 LEXUS - Oxygen Sensor Heater Control Circuit Low Bank 1 Sensor 2 Symptoms - Engine Light ON (or Service Engine Soon Warning Light)
Possible causes - Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit open shorted to ground
- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit poor electrical connection
- Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit
- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit fuse
- Faulty Engine Control Module (ECM) When is the code detected? The P0037 is set when the ECM detects an excessively low voltage through the heated oxygen sensor heater circuit P0037 LEXUS Description Oxygen Sensors (O2S) or Heated Oxygen Sensors (HO2S) need to reach a minimum operating temperature of 750 degrees F to produce an accurate voltage signal. The faster the heated oxygen sensor reaches that temperature the faster the sensor will start sending an accurate signal to the Engine Control Module (ECM).

In order to achieve the require temperature, a heater element is included inside the heated oxygen sensor. The ECM controls the heated oxygen sensor heater element based on signals from the engine coolant temperature and engine load. The ECMcontrols the heater element circuit by allowing current flow to ground.

The ECM monitors the voltage signal received through the heater element circuit and determines the state of the circuit by comparing the voltage detected with the factory specifications.

P1148 - Closed Loop Control Function Bank 1
This mean that the closed loop control function for bank 1 does not operate even when vehicle is driving in the specified condition.

The Powertrain Control Module (PCM) or Electronic Control Module(ECM) monitor the function of the Front Oxygen (O2) sensor or Air/Fuel (A/F) sensor by comparing the signal with the Rear O2 sensor.

Symptoms:
- Engine Light ON (or Service Engine Soon Warning Light)

Possible causes:
- Harness or connectors Front Oxygen (O2) sensor or Air/Fuel (A/F) sensor 1 circuit is open or shorted.
- Front Oxygen (O2) sensor or Air/Fuel (A/F) sensor bank 1
- Front Oxygen (O2) sensor or Air/Fuel (A/F) sensor bank 1 heater

Possible solution:
- Repair harness or connector. If repair is needed
- Replaced Front Oxygen (O2) sensor or Air/Fuel (A/F) sensor bank 1


Then, possible causes are faulty harness or connectors to the air fuel ratio sensor, a faulty air fuel ratio sensor (1) or faulty air fuel ratio sensor (1) heater. Most likely yes it is just faulty sensor. Just replace this devices and reset the stored codes.

Keep us updated.

you must have a check or service engine light on if any sensor is malfunctioning if no engine light is present then i suggest nothing is wrong!?