Error Code P0153 is defined as Oxygen Sensor Circuit Slow Response Bank 2 Sensor 1. This happens when the voltage signal response takes longer than specified, which is usually a result of the O2 (oxygen) sensor not properly regulating the fuel and oxygen levels.

It’s a generic trouble code, meaning, it applies to all vehicles equipped with OBD-II or made in 1996 up to present. Specifications in definition, troubleshooting and repair vary from one make and/or model to another.


This code indicates that the fuel and oxygen levels are not being properly regulated by the O2 sensor. The O2 sensor voltage switches between high and low voltage (fuel) and low voltage (air) at fast speed.

If the O2 sensor switches at a speed that is determined as slower than usual, it will cause a slow response between the O2 sensor and the PCM. When this happens, Error Code P0153 is triggered, indicating the air fuel ratio is not being properly adjusted by the O2 sensor, is not what the PCM expected, or doesn’t adjust as expected once the engine is warmed up or within a normal engine use.

Common Symptoms

The Check Engine light will be obviously triggered under this error code. However, in some cases, it may not show drivability problems other than increased or excessive fuel consumption.

Possible Causes

Error Code P0153 means one or more of the following has occurred:

  • Faulty O2 sensor
  • Broken or frayed sensor wiring leading to the O2 sensor
  • Exhaust leaks (gas leak near the O2 sensor)
  • Intake air leaks

How to Check

  1. Mechanics diagnose this error code using the OBD-II scanner; they will record all trouble codes including the freeze frame data.
  2. They will then proceed to check the exhaust including coolant and air leaks.
  3. They will also check the wires that lead to the O2 sensor and look for any signs of exposed wires.
  4. They will also inspect both the intake and vacuum hoses by going through the intake or the engine to check for leaks in the vacuum.
  5. Then they will inspect the O2 sensor for any signs of damage or contaminants that caused it to malfunction.
  6. Lastly, they will use the OBD-II scanner to check the switch for O2 sensor voltage to determine whether the voltages are actually switching as they should be or not.

How to Fix

As with most trouble codes, repairs for Error Code P0153 are pretty simple and straightforward, as you simply have to address the problems you have encountered from the diagnosis, which include:

  • Repair any exhaust leaks
  • Repair or replace damaged, shorted or frayed wires
  • For advanced cases, you will have to check the frequency and amplitude of the O2 sensor
  • Look for signs of contamination or deterioration of the O2 sensor and replace as necessary
  • Check for inlet leaks
  • Check the MAF sensor for the right operation
  • Replace the catalytic converter’s Bank 2 O2 sensor upstream

Aside from causing excessive fuel consumption, there isn’t much to worry about Error Code P0153. In some cases however, having this problem in your engine for long period of time could affect the performance of the catalytic converter.

Also, in some cases, the repair for this code requires special tools, especially when the O2 sensor commonly ceases up in the exhaust pipes. When this happens, the O2 sensor tool and heating agent are needed to complete the repair.