Attention! All work on the exhaust system must only be carried out on a cold engine, due to the risk of burns.
Monitoring compliance with exhaust gas toxicity standards is ensured by the installation of regulating oxygen concentration sensors (5 and 6, see fig. 3.29) in the exhaust gas and monitoring oxygen concentration sensors (9 and 13) in OG.
Oxygen concentration sensors are installed in the exhaust manifold before the converter. Monitoring oxygen concentration sensors are installed at the outlet of the exhaust gas converter.
The replacement of the regulating oxygen concentration sensor in the exhaust gas must be carried out in the following order. Read and fix malfunctions, eliminate malfunctions and erase information from the memory block of the ECU KSUD. Prepare fixture «11.7.020». Remove the lower part of the microfilter housing and the protective casing of the nozzles. Mark plug connectors (ShSy) and the position of the oxygen content sensors in the exhaust gas. Unclench the clamp (11 and 12) fasteners and release the wires of the sensors. Disconnect the loops from the oxygen sensors.
Using fixture «11.7.020», unscrew the sensor from the manifold.
When installing the sensor, do not confuse its location. Apply a thin and even layer of grease type «Never Seez Compound» only on its threaded part, on the new sensor it is already applied. Avoid getting grease on the surface of the sensor, which has contact with the exhaust gas. Using fixture «11.7.020» screw in the sensor (M18x1.5) and tighten it to 50 Nm (5.0 kgf·m). Pay attention to the correct laying of the sensor wires. Check stored fault messages and erase them from the fault memory. When applying anti-corrosion protection to the bottom of the body, the sensors should be insulated (cover).
The replacement of sensors for monitoring the oxygen concentration in the exhaust gas should be carried out using a similar technology. At the same time, when replacing control sensors (9 and 13, see fig. 3.29) remove the protective cover of the injectors. Release the cable from the holders, disconnect the loop and lead the cable out of the cable box on the back of the motor. In the presence of an automatic transmission, disconnecting the sensors for monitoring the operation of the converter of the 4th–6th cylinders is possible only after removing the exhaust system.
To remove and install control sensors of the 1st - 3rd cylinders, use the tool «11.7.030» (pic. 3.175), and for the 4th - 6th cylinders, use the tool «11.7.020».
Pay particular attention to the correct laying of the cables for the oxygen sensors in the exhaust gas.