P0136 hey - if I replace O2 sensor, and everything else would be ok with the entire system - the check engine light will go away by itself, or I need to reset it with some device?

You still have a problem with all the O2 sensors Bbank 1 Sensor 1, Bank 2 Sensor 1 and Bank 2 Sensor 2) - if they are all the correct ones and are correctly installed and connected, then you need to carefully check the wiring harness and wire connections from them to the ECU. the P0300 just means random engine misfires.

P0136 - Oxygen O2 Sensor Circuit Low Voltage

Means that either your O2 sensor needs replacement, or the wires to it are going bad.

Code 136 is for a problem with the O2 sensor mounted in the exhaust pipe after the catalytic converter.
The sensor would need to be checked with a scanner.

P0442 FORD - Evaporative Emission System Leak Detected Small Leak

Possible causes- Missing or loose fuel cap
- Incorrect fuel filler cap used
- Fuel filler cap remains open or fails to close
- Foreign matter caught in fuel filler cap
- EVAP canister or fuel tank leaks
- EVAP system hose leaking
- Fuel tank leaking
P0136 - O2 Sensor Circuit Malfunction Bank 1 Sensor 2
Possible causes- Rear Heated Oxygen Sensor Bank 1 harness is open or shorted
- Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection
- Faulty Rear Heated Oxygen Sensor Bank 1
- Inappropriate fuel pressure
- Faulty fuel injectors
- Intake air leaks may be faulty
- Exhaust gas leaks

P0141 FORD - O2 Heater Circuit Bank 1 Sensor 2

Possible causes- Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2
- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit fuse
- 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 Engine Control Module (ECM)

A code P0136 may mean that one or more of the following has happened:

• Faulty O2 sensor or a leak in the exhaust close to O2 sensor
• Short to voltage on O2 signal circuit
• Open in circuit or high resistance caused by corrosion in the connector or other wiring to the O2 sensor.

The exhaust system should be inspected and the circuits to the sensor should be tested before spending any money on an O2 sensor. This COULD be caused by the sensor itself, but then again, maybe not.

What does that mean? Essentially the same as P0137, a P0136 code refers to the second oxygen sensor on Bank 1. The O2 oxygen sensor produces a voltage between .1 mV and .9 mV. The ECM monitors O2 sensor voltage and determines if exhaust is lean or rich. O2 sensor voltage is high when exhaust is rich and low when exhaust is lean. The ECM monitors this voltage and increases or decreases fuel injector pulsewidth according to engine fuel/air ratio. If the ECM detects low HO2Sensor voltage for an extended period, it will set P0136 Conditions required to set: HO2 sensor voltage is low for longer than 2 minutes (minutes depend on model of vehicle. Could be up to 4 minutes)
Symptoms There may be no visible symptoms to the driver. Poor fuel mileage, possible misfire, depending on O2 sensor position when sticking.
Causes A code P0136 may mean that one or more of the following has happened:

• Faulty O2 sensor leak in exhaust close to O2 sensor
• Short to voltage on O2 signal circuit
• Open in circuit resistance caused by corrosion in connector

Possible Solutions

• Replace the second oxygen sensor on bank 1
• Repair open or short in signal circuit
• Clean corrosion from connector

A P0304 code means that the the car's computer has detected that one of the engine's cylinders is not firing properly. In this case it's cylinder #4.
Symptoms Symptoms may include:

• the engine may be harder to start
• the engine may stumble / stumble, and/or hesitate
• other symptoms may also be present

Causes A code P0304 may mean that one or more of the following has happened:

• Faulty spark plug or wire
• Faulty coil (pack)
• Faulty oxygen sensor(s)
• Faulty fuel injector
• Burned exhaust valve
• Faulty catalytic converter(s)
• Running out of fuel
• Poor compression
• Defective computer

Possible Solutions If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.
If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.

Replace the O2 sensor first and see if that helps clear the vehicle up some. Some times these codes will trigger other codes and these are the issues that you will get.

p0136 02 sensor malfunction is (bank 1 sensor 2)-- replace 2nd 02 sensor thats in exhaust system. If it is a four cyclinder, then there is only one bank. if its a six then bank 1 is on the side of # 1 cylinder. bank 1 sensor 2 is after convertor. have a good day !

P0155: O2 Sensor heater Circuit Malfunction (bank2 ) Sensor 1.

P0141: O2 Sensor heater Circuit Malfunction (bank1 ) Sensor 2.

P0135: O2 Sensor heater Circuit Malfunction (bank1,Sensor1)

P0136: O2 Sensor Circuit Low voltage (bank1) Sensor 2.

P0443 : Evaporative Emission control System Purge control valve.

P1451: Eavporative Control System Canister vent solenoid Circuit Malfunction.

P0161: O2 Sensor Circuit Low voltage (bank2,Sensor2)

P1409: Electronic Vacuum Regulator (EVR) control circuit malfunction.

change the O2 sensors first,Then check the the EGR Vacuum regulator for any Malfunction. Good luck

Your auto has four O2 sensors. Two upstream and two downstream; With two banks. Bank 1, sensor 1...and bank 2, sensor 1 are the two upstream (exhaust manifold before the catalytic). Bank 1, sensor 2 and bank 2, sensor 2 (other side of catalytic)

Code 1131= upstream; bank 1..sensor 1
Code 1151= upstream; bank 2..sensor 1
Code P0136 (generic code) bank 1..sensor 2 (questionable)

I wouldn't spend the money to purchase 3 sensors. Highly unlikely all three are bad; Cost is about $40/ ea.
Since there isn't a code for the cat's themselves, I would suspect the O2 circuit is malfunctioning. The rough idle is another clue.


Take an ohmmeter set it on X10 scale and measure the resistance from engine to body and body to negative post on battery terminal. You should read zero ohms (full needle deflection). If you do go buy two upstream O2 sensors. If you read
open or a high resistance run two straps from eng. to body...and body to neg.batt. post.

FixYaWIZ................saailer



I’m happy to help further over the phone at https://www.6ya.com/expert/david_6df67de3b14de867

P0136 = O2 Sensor Circuit Malfunction (Bank 1, Sensor 2)

Which would be the oxygen sensor after the converter.