Air & Fuel Mixture ControlOBD2 Codes

P0136 – Meaning, Causes, Symptoms, & Fixes

Code P0136 Definition

Oxygen Sensor Circuit Malfunction (Bank 1, Sensor 2)

What Does P0136 Mean?

Your car has oxygen (O2) sensors that measure the amount of oxygen present in your exhaust. Based on the measurements taken, the O2 sensor will fluctuate between a high(rich) and low(lean) voltage reading. Your Engine Control Module (ECM) uses the voltage levels provided by your O2 sensors to regulate your engine’s fuel injector pulse. If you are seeing code P0136, it means that the O2 sensor behind your catalytic converter on bank 1 is malfunctioning.

What Are The Symptoms Of Code P0136?*

  • Check Engine Light
  • Decrease in MPG
  • Increased tailpipe emissions

*No noticeable adverse conditions in some cases

What Is The Cause Of Code P0136?

  • Faulty Bank 1 O2 sensor 2
  • Exhaust leak in front of sensor 2
  • Intake Leak
  • Corrosion in connecter
  • Frayed or broken wiring

How Severe Is Code P0136? – Moderate

Driving with trouble code P0136 is acceptable but only for a short period of time. Driving with this code for an elongated period of time could result in greater engine or catalyst damage.

Code P0136 Common Diagnosis Mistakes

Replacing the O2 sensor without checking for any intake or exhaust leaks or loose connections.

Tools Needed to Diagnose:

How To Diagnose And Repair Code P0136?

Difficulty of Diagnosis and Repair – (2 out of 5)

  1. A sensor is needed for this next action, and the FIXD Sensor is perfect for it. Scan codes and document freeze frame data then clear codes to verify failure.
  2. Note if the O2 sensor is rapidly or slowly switching from low to high voltage. This could indicate a faulty O2 sensor.
  3. Check for any broken or shorted wiring in relation to the O2 sensor. If there is any broken or shorted wiring, make sure to repair or replace it.
  4. Check for any vacuum leaks in the engine or any holes in the exhaust that could lead to air escaping from the engine. Repair any leaks or holes you find.
  5. At this point, if there are no intake or exhaust leaks, you should replace the bank 2 sensor 2 oxygen sensor.

Estimated Cost of Repair

For error code P0136, one or more of the below repairs may be needed to solve the underlying issue. For each possible repair, the estimated cost of repair includes the cost of the relevant parts and the cost of labor required to make the repair. 

  • Oxygen sensor $200-$300
  • Exhaust repair $100-$200 (if welded to repair)
  • Vacuum leak $100-$200

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  1. Needed diagnostic info for a similar (yet different) P0137 CEL code

    1. No problem Ryan! Here is a link for our article on Check Engine Light code P0137.

      1. How much to replace all O2 sensor for 1999 ml 320 ?? Parts and labor ??

        1. Hi, just wanted to ask how do I Scan codes and document freeze frame data then clear codes to verify failure. And how do I find out if the o2 sensor is slowly switching to high or low voltage?

        2. How to replace P0136 sonsor is failed and light engen

      2. Have p0134 code can it be catalytic converter or fuel pressure..pit fuel pressure gauge on and it goes around twice and stats their..pit a bypass on fuel gauge and let has go into engine and into a 5 gal bucket and then had 55 to 60 lbs of pressire

  2. My car was running fine ,but check engine light was ,on b4 I got the car some one had a home made cold air intake on it ,I replaced it the other day with the proper one ,no air leaks etc,its properly but afterwards, car idles norm but will shut off sometimes when slowing and hesitating sometimes in 5th gear when at cruising speed 40/45 mph had it code checked and got PO137, OXY SENSOR BANK1 SENSOR 2 LOW VOLT, PO138 OXY SENSOR BANK 1 SENSOR 2 HIGH VOLT ,P1235 ,AND PO300 ,

  3. Please show me where is located the catalytic 02 sensor for my Dodge Ram 1500 2003 4.7 engine. Also need to now where is located the vacuum.

  4. I’m getting this code, I have the FIXD app and device, I cleared the code, will I fail emissions test with this code popping up?

    1. Hello Brian,

      If the code is emissions related, it cannot be cleared by a scanner. The light will come back on if the problem persists. It is recommended to have this code repaired as soon as possible as continuing to drive could risk greater damage to your vehicle’s engine.

      I hope this helps!

  5. I had a dirty mass air flow sensor that caused this error.

    1. which code are you referring to :p0136 or p0137? My highlander has a new rear oxygen sensor and I still got p0136. thanks,

  6. Where is the O2 sensor located on my Ford Escape 2003?
    Many thanks

  7. Where are the 4 O2 sensors located on a 2013 Nissan Pathfinder?

  8. PO137 Bank 1 SENSOR

  9. FIXD helped me with my engine trouble

    1. Thank you so much for using FIXD, Leo! We are so happy we were able to help you with your engine trouble. Happy and safe driving 🙂

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