The engine management system sensors, during engine operation and when starting the engine, constantly monitor and maintain the specified parameters and transmit signals to the electronic control unit.
Removing and refitting the crankshaft position sensor
The sensor is installed in the front cover of the cylinder block on the right-hand side. The sensor is of the inductive type, with a magnetic core; it is secured with an M6 screw and sealed with a rubber O-ring.
If the crankshaft position sensor fails, the engine will not start.
If the sensor works intermittently (poor starting or engine misfires), check the magnetic end of the sensor for foreign particles.
If foreign particles are present, clean the sensor.
To remove the sensor, a flat-blade screwdriver and a 5 mm hex key are required.
We disconnect the battery negative terminal.
We slide the retaining tab of the wiring harness connector with a screwdriver.
We squeeze the catch.
We disconnect the wiring harness connector from the crankshaft position sensor.
We undo the sensor securing screw.
We remove the sensor.
We refit the new crankshaft position sensor in the reverse order. Screw tightening torque: 8 N·m.
Camshaft position sensor
The camshaft sensor is installed in the opening of the upper timing chain cover, at the rear of the engine on the left-hand side. The sensor is of the inductive type, secured with an M6 screw and sealed with a rubber O-ring.
If the camshaft sensor stops working, the controller uses only the crankshaft sensor signals.
A screwdriver and a 5 mm hex key are required.
We disconnect the battery negative terminal.
We slide the retainer of the harness connector.
We squeeze and disconnect the harness connector from the sensor.
We undo the sensor (CPS) securing screw.
We remove the camshaft position sensor.
We refit the sensor in the reverse order.
We lubricate the O-ring with clean engine oil. Screw tightening torque: 8 N·m.
Combined boost pressure/intake air temperature sensor in the intake manifold
The intake manifold air pressure and temperature sensors are combined into a single unit.
The sensor is installed on top of the engine intake pipe.
If the combined sensor is faulty, the controller limits the boost pressure and engine power decreases.
We disconnect the battery negative terminal.
We squeeze the catch of the harness connector.
We disconnect the harness connector from the sensor.
We undo the combined sensor securing screw.
We remove the sensor from the engine by pulling it vertically upwards.
When removing the sensor, do not damage the O-ring or the plastic shroud around the sensor tip.
Do not use a lever so as not to damage the plastic shroud.
We check the harness connector and the combined sensor for the absence of the following defects:
- cracks or damage on the body;
- missing or damaged connector seals;
- dirt, foreign particles or moisture on the connector contacts;
- corroded, bent, broken, pushed-in or widened connector contacts.
We check the sensor tip for the absence of soot, deposits and carbon.
If necessary, remove the soot with compressed air.
Do not replace the sensor because of soot on it.
We fit the sensor to the engine. We tighten the screw to 6 N·m.
Atmospheric pressure sensor
The sensor is attached to the wiring harness without being secured to the engine with screws, on the left-hand side.
If the sensor fails, the controller operates on a backup programme using the calculated average atmospheric pressure value.
We disconnect the battery negative terminal.
We cut the clamp securing the atmospheric pressure sensor to the engine wiring harness.
We slide the retaining tab of the harness connector.
We squeeze the catch.
We disconnect the atmospheric pressure sensor from the connector.
The sensor can only be checked with a diagnostic tester.
We fit the atmospheric pressure sensor and secure it to the engine wiring harness with a new clamp.
Fuel pressure sensor
The fuel pressure sensor is located on the rail, screwed into an opening. If the fuel pressure sensor fails, the high-pressure fuel pump does not work.
To remove the sensor, the pressure in the fuel line must be released.
We squeeze the catch of the fuel supply pipe end fitting to the high-pressure pump.
We disconnect the pipe.
We start the engine and let it run until it stops completely (this releases the pressure in the fuel line).
We disconnect the battery negative terminal.
We squeeze the catch.
We disconnect the harness connector from the fuel pressure sensor.
Using a 27 mm spanner, we unscrew the sensor from the fuel rail.
We inspect the connector and the sensor itself for the absence of the following defects:
- cracks or damage on the connector body;
- missing or damaged connector seals;
- dirt, foreign particles or moisture on the connector contacts;
- corroded, bent, broken, pushed-in or widened connector contacts.
We check the fuel pressure sensor for the absence of the following damage:
- damage to the contact surface on the fuel line;
- damage to the contact surface on the sensor;
- damage to the thread.
We fit a new fuel pressure sensor. Sensor tightening torque: 70 N·m.
We start the engine and check the tightness of the sensor connection.
Replacing the coolant temperature sensor
The coolant temperature sensor, intended to determine the coolant temperature in the engine, is installed in a boss of the thermostat housing located closer to the cylinder block.
The second sensor, installed in the boss of the thermostat housing closer to the radiator, serves the coolant temperature gauge in the instrument cluster.
The control unit, based on the coolant temperature sensor reading, changes the start of fuel injection and controls the air heater in the intake pipe.
If a sensor fault occurs, the controller takes the average temperature value.
We prepare the vehicle for the work.
We disconnect the battery negative terminal.
We remove the auxiliary drive belt (article — Replacing the auxiliary drive belt).
We undo the bolt securing the upper intermediate roller to the cylinder head.
We remove the roller.
We press the catch.
We disconnect the harness connector from the coolant temperature sensor.
We unscrew the sensor.
We take it out of the threaded opening of the thermostat housing.
After unscrewing the sensor, immediately insert a plug or screw in a new sensor so as not to drain the coolant.
We fit a new sensor in the reverse order. The rubber sealing ring must be replaced with a new one.
Before connecting the harness connector, it must be carefully inspected for defects.
