The oxygen sensor, or lambda probe, is a critical element of the engine management system on a crossover Nissan Murano second generation (Z51 body). It is this component that provides feedback to the control unit, allowing the system to maintain the ideal balance of the fuel mixture for efficient combustion. On models with the VQ35DE engine that were installed on this car, the reliability of the electronics is quite high, but operation in our conditions inevitably leads to wear of the sensitive element.
Understanding of operating principles lambda probe will help the owner to notice the onset of problems in time before they lead to serious damage to the catalyst or engine. Ignoring malfunction signals can provoke not only an increase in fuel consumption, but also the failure of expensive exhaust system components. Owners Nissan Murano Z51 It is important to know how to distinguish natural aging of the sensor from problems with the wiring or the motor itself.
This article examines in detail the design features of oxygen sensors on your car, specific error codes that may appear on the dashboard, and a step-by-step algorithm for self-replacement. We will also touch on the issue of choosing between original parts and high-quality analogues, so that you can make an informed decision when purchasing spare parts.
Purpose and principle of operation of the lambda probe on Murano Z51
There are at least two oxygen sensors installed in your vehicle's exhaust system: the first is located before the catalytic converter, and the second is located after it. First lambda probe is responsible for correcting the composition of the fuel-air mixture in real time, informing the ECU about the amount of oxygen remaining in the exhaust gases. The second sensor monitors the efficiency of the catalyst by comparing the composition of gases before and after filtration.
On Nissan Murano with a 3.5 liter engine, a wideband sensor (A/F sensor) is used at the input, which works on a more complex principle than a conventional lambda probe. It is able to measure not only the presence of oxygen, but also its exact amount, which allows the control unit to maintain a stoichiometric ratio of 14.7:1 with high accuracy. This is critical for the operation of the direct injection system and reducing exhaust emissions.
If the first sensor does not work correctly, the computer switches to emergency mode using average values from memory, which inevitably leads to excessive fuel consumption.
The second sensor, located after the catalyst, usually operates like a regular two-wire or four-wire probe, simply checking to see if the catalyst is reducing nitrogen oxides and hydrocarbons.
Malfunction of any of these elements upsets the delicate balance of the engine, causing jerking, misfires and increased exhaust system temperatures.
- ⚡ The first sensor (A/F) - 4 wires, is responsible for the mixture and power.
- 🛡️ The second sensor - 4 wires, is responsible for the efficiency of the catalyst.
- 🌡️ Both elements require heating to operating temperature (about 300-400°C) to start.
⚠️ Attention: Never try to “deceive” the system by disconnecting or flashing the ECU without replacing the catalyst. On Nissan Murano Z51 This will result in an immediate Check Engine light and failure to pass inspection, as well as destruction of the piston group due to the incorrect mixture.
The main signs of a malfunctioning oxygen sensor
Recognize the problem with lambda probe on Nissan Murano This can be determined not only by the light on the instrument panel, but also by changes in the behavior of the car while driving. The most obvious indicator is unstable engine operation at idle, when the tachometer needle begins to float, and the engine may stall when stopping at a traffic light. This happens because the control unit does not receive correct data on the composition of the mixture and “fills” fuel into the cylinders randomly.
Another sure sign is a sharp increase in fuel consumption. If you notice that you're filling up your tank more often than usual without changing your driving style, it's worth checking your engine management system. The ECU, without receiving confirmation from the sensor, begins to enrich the mixture “just in case,” which leads to excessive fuel consumption by 15-20%. There may also be a smell of unburned gasoline coming from the exhaust pipe.
Owners often confuse the symptoms of a malfunctioning lambda probe with problems with spark plugs or coils, but the characteristic black soot on the spark plugs and smoke from the exhaust often indicate over-enrichment.
Sometimes the Check Engine light may come on on the dashboard, but the car continues to drive normally, which creates a false sense of security and delays a service visit.
- 🔥 The smell of unburned fuel from the exhaust pipe.
- 📉 Loss of acceleration dynamics and jerking when pressing the gas.
- 🚨 Errors P0130-P0135 (front sensor) or P0030-P0036 (heating).
- Check Engine light on
- Increased fuel consumption
- Jerks during acceleration
- The car stalls at idle
- Nothing worries
Diagnostics and reading error codes
To accurately diagnose the malfunction, you must connect the OBDII diagnostic scanner to the car connector. On Nissan Murano Z51 This connector is usually located under the dash on the driver's side, near the fuse box. Without special equipment, it is extremely difficult to determine which sensor has failed, since the symptoms of different errors often overlap.
The most common error codes for the front sensor (Bank 1 Sensor 1) are P0130 (open circuit), P0131 (low signal), P0132 (high signal), and P0133 (slow response). The second sensor (Bank 1 Sensor 2) is characterized by errors P0030, P0031, P0032 and P0033. It is important to note that a Heater Circuit error often indicates a problem with the heating element itself inside the sensor, rather than with the sensing part of the sensor.
Sometimes the error can be “floating”, appearing only when the engine warms up or at certain speeds, which requires a more thorough check with an oscilloscope.
Self-testing with a multimeter is possible, but requires knowledge of the pinout and an understanding of how the voltage changes depending on the engine load.
It must be taken into account that the error can be caused not only by the sensor, but also by damage to the wiring or oxidation of the contacts in the connector.
| Error code | Decoding | Probable Cause | Seriousness |
|---|---|---|---|
| P0133 | Bank 1 Sensor 1 Slow Response | Wear of the sensitive element, clogged catalyst | Average |
| P0135 | Bank 1 Sensor 1 Heater Circuit | Heater burnt out, open circuit | High |
| P0031 | Bank 1 Sensor 2 Heater Low | Problem with heating of the second sensor | High |
| P0420 | Catalyst System Efficiency | Catalyst or second sensor faulty | Average |
⚠️ Attention: Error P0420 often indicates the ineffectiveness of the catalyst, but at a mileage of more than 150,000 km it can be caused precisely by a “tired” second oxygen sensor that incorrectly reads the data.
Selection of original sensor and analogues
When replacing the oxygen sensor with Nissan Murano The owner is faced with a choice: buy an original part or a high-quality analogue. The original sensor from Nissan (often produced by NTK/NGK) has perfect calibration and is guaranteed to last a long time, since its materials were selected by the automaker's engineers. However, the price of original parts can be quite high, especially for a wideband A/F sensor.
Analogs from manufacturers like Bosch, Denso or NGK can be an excellent alternative if you choose a model with the corresponding catalog number. It is important to pay attention to the length of the wire and the type of connector, since even with identical sensor characteristics, the physical connection may not be suitable. Low-quality Chinese copies often have poor insulation and quickly fail due to vibration and thermal stress.
- 🔧 Denso is a direct competitor of the original, often installed on the assembly line.
- ⚙️ Bosch are reliable analogues, but require careful compatibility testing.
- ⚠️ Cheap Chinese brands - the risk of quick breakdown and incorrect operation of the ECU.
When purchasing an analogue, be sure to check the wire number and connector shape with the original. Even if the sensor fits the thread, the incorrect length of the wire may not allow it to be installed in its original location without tension.
Step-by-step instructions for replacing the sensor
Replacing the oxygen sensor with Nissan Murano Z51 - a task that can be performed independently, if you have the necessary tools and access to the bottom of the car. Before starting work, be sure to let the engine cool down, as the exhaust system components are heated to dangerous temperatures. Accessing the front sensor may require removing the engine guard and possibly some subframe components.
Disconnect the battery terminal first to avoid short circuit. Find the location of the sensor: the front sensor is located in the manifold or immediately after it, before the catalyst. Disconnect the electrical connector of the sensor by pressing the latch and unscrew the sensor using a special puller key with a slot for the wire. If the sensor is stuck, use a penetrating lubricant and give it time to work.
☑️ Preparing to replace the sensor
Install the new sensor using a special heat-resistant paste on the threads to avoid sticking in the future.
Tighten the sensor to the torque specified in the instructions (usually about 40-50 Nm), but do not overtighten so as not to damage the thread.
Connect the connector, making sure that the latch is securely fastened, and return the removed protection parts to their place.
⚠️ Attention: When unscrewing the old sensor, be extremely careful with the wire. If you accidentally break or fray the wire insulation, the new sensor will fail very quickly.
Adaptation and error reset after replacement
After installing a new sensor, you should not immediately rejoice and turn off the engine. The control unit requires time to learn new parameters. In some cases, it is enough to simply drive a few kilometers in different modes for the ECU to adapt. However, to completely reset the fuel mixture adaptations and clear errors, it is better to use a diagnostic scanner.
Enter the error reset command through the scanner or disconnect the battery for 15-20 minutes, although this method is not always effective for resetting long-term adaptations. After the reset, start the engine and let it idle until it warms up completely. Make sure the Check Engine light is off and the engine speed is stable.
Correct adaptation of a new sensor is not just resetting errors, but the process of teaching the ECU new mixture characteristics, which takes from 10 to 50 km.
If the error does not disappear immediately, check the quality of the connection and make sure that the sensor was not damaged during transportation.
In some cases, a forced reset of adaptations through the menu is required Service Menu or specialized Nissan Consult software.
Questions and answers
Is it possible to drive with a faulty lambda probe?
Technically it is possible, but this will lead to increased fuel consumption, loss of power and the risk of catalyst failure. Long-term use may damage the spark plugs and ignition coils.
How often do you need to replace the oxygen sensor on your Nissan Murano Z51?
Original sensors usually last from 100,000 to 150,000 km. However, the quality of the fuel and the condition of the engine can shorten this period. It is recommended to check their condition during scheduled maintenance after 100 thousand km.
Why does P0420 appear after replacing the sensor?
The P0420 code often means that the catalytic converter is ineffective. If you only replaced the second sensor and the catalyst is already worn out, the error will return. Sometimes it is necessary to replace the catalyst itself or install a software trick (if permitted by law).
Is it possible to use a universal sensor instead of the original?
Universal sensors (for example, from Bosch) can be used if you know how to properly crimp contacts and select wires. However, for a wideband A/F sensor (front), this is highly discouraged due to the difficulty of calibration.
Why is a heater needed in an oxygen sensor?
The heater is needed to quickly bring the sensor to operating temperature. Without it, the sensor will not start working until the exhaust gases warm it up, which increases the operating time on a rich mixture during a cold start and increases toxicity.
Hidden information about warm-ups
On modern Nissan engines, the catalyst warms up very quickly due to the valve timing, so the sensor must be operational from the first seconds of engine operation for the EGR system to operate correctly.