Guide To P0138 OBD Error Code Solutions

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The P0138 is a trouble code which would indicate that the O2 sensor for bank 1 sensor 2 has failed to have a lower voltage output below 1.2 volts for more than 10 seconds showing a lack of oxygen in the exhaust system.

The P0138 error code can be defined as O2 sensor circuit high voltage bank 1, sensor 2. It is normally located in the catalytic converter, before the muffler, in the car exhaust system. The oxygen levels are monitored in this sensor in the exhaust stream. This would gauge the proper fuel efficiency as well as check that the engine is maintaining correct air fuel ratio for a clean burn.

What causes this problem with the 02 Sensor Circuit High Voltage (Bank I Sensor 2)?

• The engine control module might see the voltage of the oxygen sensor for bank 1 sensor 2 above 1.2 volts when the ECM has commanded the fuel to a targeted lean condition on that bank of the engine.
• The voltage high problem is detected by the engine control module and check engine light is turned on
• The engine control module uses other oxygen sensors to try and control the fuel injection with their values

1. Oxygen Sensor - Faulty Oxygen Sensor can be the reason why P0138 code is flashing. Visit us to purchase top notch Oxygen Sensor online.
2. Mass Air Flow sensor - It is an important auto part which needs full care. A faulty Mass Air Flow sensor can be a reason behind the flashing up of P0138 code.
3. Manifold Absolute Pressure sensor - OBD Code P0138 can appear because of faulty Manifold Absolute Pressure sensor.
4. Exhaust Parts - Do you remember when was the last time you got your car Exhaust Parts checked up? A damaged Exhaust System can cause a lot of issues like displaying P0138 code.
5. Powertrain Control Module - P0138 code can display due to some issues in the Powertrain Control Module. So, it is very important to replace the damaged Powertrain Control Module with us at equitable prices.
6. Engine Control Module - Have you ever thought when was the time you got your Engine Control Module inspected properly? A defective Engine Control Module can cause a lot of issues like displaying P0138 code.
7. Fuel Pump - Poor Fuel Pump can cause a lot of difficulties, so why not get it replaced at time?

We care for our customers and that’s why we can totally understand your problem. That’s the reason why we have listed out some major symptoms behind the flashing up of OBD Code P0138. They are mentioned here as follows:

Common Symptoms

• The car engine can start running lean during the testing of the sensor to correct the problem and may hesitate or misfire
• The check engine light can start illuminating
• You may have to face problems related to engine running depending on failure cause of the rich condition

It is very important to fix the fault code P0138. So here are some ways with which you can correct this issue:

• The O2 sensor for bank 1 sensor 2 should be replaced
• You must repair or replace the wiring or connection to the O2 sensor for bank 1 sensor 2
• You must replace the catalyst in front of the sensor
• A leaking injector should be replaced

Don’t get tensed if you are still facing any of these issues as we care for our customers and that’s why we offer a good range of catalytic converter, fuel pump, relay wiring harness and a lot more. We are sure that now all your issues would be resolved.

• The first and the foremost thing which should be do is that the codes should be scanned and document freeze frame data then clear the codes to verify failure
• After that the oxygen sensor data should be monitored to see if the voltage is switching back and forth between low and high at a fast rate compared to other sensors
• Check the oxygen sensor wiring and the harness connections for any corrosion in the connections
• Carefully inspect the oxygen sensor for any physical damage or fluid contamination
• Leakage in the exhaust should be checked before the sensor
• Follow the manufacturer's specific pinpoint tests for carrying out further diagnosis

Common Mistakes When Diagnosing The P0138 Code

• You can use O2 sensor 1 for bank 1 to diagnose O2 sensor 2 for bank 1 by looking at both sensors operation for comparison. The operation should be nearly the same, except sensor 2 should have a lower O2 reading since the catalyst should burn off the excess fuel as well as oxygen
• The oxygen sensor should be properly checked for oil or coolant contaminants from any engine leakage
• The catalyst for damage should be checked or it being clogged that can cause erratic sensor readings