The engines installed on Renault/Dacia Sandero vehicles are equipped with an electronic engine management system with multiport fuel injection.

This system ensures that the latest emissions and fumes standards are met while maintaining high driving performance and low fuel consumption.

The cars are equipped with a feedback engine control system (the presence of a catalytic converter and an oxygen concentration sensor).

We remove the sensors and the electronic engine control unit for inspection, as well as for replacement.

Removing the electronic engine control unit

We prepare the car for the task, disconnect the negative battery terminal

Replacing Renault Sandero engine management system components

With a 10 socket head, unscrew the two nuts securing the computer

Replacing Renault Sandero engine management system components

Pull out the latch in the direction shown by the arrow

Replacing Renault Sandero engine management system components

Disconnect the wiring block and remove the electronic unit

Install parts in reverse order

Replacing the crankshaft speed sensor

If the crankshaft sensor fails, the engine stops working.

In the instrument cluster, a signal lamp lights up and the controller stores a fault code in memory.

Replacing Renault Sandero engine management system components

Using a screwdriver, we press the lock of the wire block

Replacing Renault Sandero engine management system components

Disconnecting the sensor wiring harness block

Replacing Renault Sandero engine management system components

Using a 10 key, we unscrew the two sensor mounting bolts

Replacing Renault Sandero engine management system components

Remove the sensor

Install the sensor in reverse order.

After replacing the crankshaft sensor or flywheel, you need to make sure that the fuel injection system is working correctly using a special tool.

Verification includes the following:

  • - deceleration of the car with a cut in the fuel supply in II, III, IV or fifth gear at a speed of 3500-3000 min -1 for at least 2s;
  • - repeated deceleration with fuel supply interruption in II, III, IV or fifth gear at a speed of 2400-2000 min -1 for at least 3 s;
  • - check for fault codes and, if necessary, troubleshoot;
  • - erase codes.

Replacing the coolant temperature sensor

The coolant temperature sensor is installed in the cylinder head near the first cylinder.

Replacing Renault Sandero engine management system components

The sensor is a thermistor, as the temperature increases, the resistance of the sensor decreases.

Depending on the sensor signal, the optimal value of the mixture enrichment is set.

To remove and test the sensor, you will need a 21 wrench, a flat-blade screwdriver, a tester, a thermometer.

Disconnect the negative battery terminal

Drain the coolant (article - Replacement and engine coolant Renault Sandero)

Replacing Renault Sandero engine management system components

We press the clamp of the sensor wiring harness block

Replacing Renault Sandero engine management system components

Disconnect the wiring harness from the coolant temperature sensor

Replacing Renault Sandero engine management system components

Loosen the sensor with a wrench and unscrew it by hand

Install the parts in reverse order.

Pour coolant into the engine cooling system.

Replacing the throttle position sensor

The sensor is a potentiometer that is mounted on the throttle shaft.

Rotation of the throttle axis changes the voltage of the sensor signal, by which the electronic unit determines the degree of throttle opening.

If there is a problem with the engine idling or a deterioration in throttle response, check the sensor and its connector.

To remove the sensor, you will need a Torx T20 key, tester

Disconnect the negative battery terminal

Remove the air filter (article - How to replace the Renault Sandero engine air filter element)

Replacing Renault Sandero engine management system components

We press the latch and disconnect the wire block from the sensor

Replacing Renault Sandero engine management system components

Connect the tester to terminals "B" and "C" of the sensor in resistance measurement mode

Replacing Renault Sandero engine management system components

Measure the resistance at the terminals with the throttle fully closed.

Replacing Renault Sandero engine management system components

It should be 2.3-2.4 kOhm.

Turn the throttle by hand until it is fully open and measure the resistance again.

Resistance should be 1.3-1.4 kOhm.

Replacing Renault Sandero engine management system components

To replace the sensor, unscrew the two mounting bolts

Replacing Renault Sandero engine management system components

Remove the throttle position sensor

Install the sensor in reverse order.

Replacing the absolute pressure (vacuum) sensor in the intake pipe

The sensor detects the change in pressure (vacuum) in the intake pipe depending on the engine speed and converts it into an output signal voltage.

Depending on the sensor signal, the controller calculates the amount of air entering the engine.

Disconnect the negative battery terminal

Replacing Renault Sandero engine management system components

Press the wire block retainer

Replacing Renault Sandero engine management system components

Disconnect the wiring harness from the sensor

Replacing Renault Sandero engine management system components

Remove the sensor (the sensor fitting is installed with an interference fit in the intake pipe hole)

Install the sensor in reverse order

Replacing the air temperature sensor in the intake pipe

Replacing Renault Sandero engine management system components

The sensor is an NTC thermistor (the electrical resistance of the sensor decreases with increasing temperature).

The ECU regulates the amount of injected fuel depending on the signal from the sensor.

Replacing Renault Sandero engine management system components

On the K4M engine, the air temperature sensor is mounted on the receiver and removed as well

Disconnect the negative battery terminal

Remove the air filter (article - How to replace the Renault Sandero engine air filter element)

Replacing Renault Sandero engine management system components

Disconnect the wiring harness block from the sensor by squeezing the spring clip with your fingers

Replacing Renault Sandero engine management system components

Pry off the sensor with a screwdriver

Replacing Renault Sandero engine management system components

Remove the sensor from the intake manifold

Install the sensor in reverse order

Removing and installing knock sensor

The knock sensor is installed between the second and third cylinders.

Replacing Renault Sandero engine management system components

The sensor detects vibrations, shocks in the engine.

We install the car on a lift or a viewing ditch

Disconnect the negative battery terminal

Replacing Renault Sandero engine management system components

Squeeze the latch and disconnect the wire block from the sensor

Replacing Renault Sandero engine management system components

Use a 24 key to unscrew the knock sensor

Replacing Renault Sandero engine management system components

And remove the sensor.

Install the parts in reverse order.

Replacing the control sensor for oxygen concentration in exhaust gases

The sensor is installed on the exhaust manifold.

The sensor measures the amount of oxygen in the exhaust gases and converts the measured value into a signal voltage that is supplied to the controller.

Using the signals from the sensor, the ECU controls the fuel injection in such a way as to obtain the calculated composition of the fuel mixture.

The oxygen concentration sensor is a key component m exhaust gas cleaning system, you need to use only high-quality spare parts.

Disconnect the negative battery terminal

Replacing Renault Sandero engine management system components

Press the wire block retainer

Replacing Renault Sandero engine management system components

Disconnecting the wire block

Replacing Renault Sandero engine management system components

Remove the block from the bracket by sliding it forward

Replacing Renault Sandero engine management system components

Unscrew the three nuts securing the thermal screen

Replacing Renault Sandero engine management system components

Remove the thermal screen

Replacing Renault Sandero engine management system components

Remove the wire from the holder

Replacing Renault Sandero engine management system components

Weaken the sensor with the key 22

Replacing Renault Sandero engine management system components

Unscrew the sensor from the exhaust manifold

Install the sensor in reverse order. Sensor tightening torque 40-60 Nm.

Sensor threads should be lubricated with graphite grease.

Removing the diagnostic oxygen sensor

The diagnostic sensor is installed after the catalytic converter.

The sensor works on the same principle as the control sensor.

The signal generated by the diagnostic oxygen sensor indicates the presence of oxygen in the exhaust gases after the converter.

If the converter is working properly, the readings of the diagnostic sensor will differ significantly from the readings of the control sensor.

Replacing Renault Sandero engine management system components

Disconnect the block of wires by pressing the latch

Replacing Renault Sandero engine management system components

Weaken the sensor with the key 22

Replacing Renault Sandero engine management system components

Unscrew the sensor

Install the sensor in reverse order

Removing the vehicle speed sensor

The speed sensor is mounted on the gearbox and is a Hall effect sensor.

The sensor sends a pulse signal to the ECU proportional to the speed of the drive wheels.

Replacing Renault Sandero engine management system components

We press the lock of the sensor wire blocka

Replacing Renault Sandero engine management system components

Disconnect the wiring harness from the speed sensor

Replacing Renault Sandero engine management system components

Pry off the sensor with a screwdriver

Replacing Renault Sandero engine management system components

Remove the sensor from the gearbox housing.

Install the sensor in reverse order.