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Exhaust systems and reduce emissions
general information Exhaust System The exhaust system consists of exhaust manifold, front exhaust pipe, catalytic converter, muffler and exhaust pipe. Systems for reducing emissions The principle of operation of the engine management system is constructed in such a way as to get the most out of the engine with minimum fuel consumption and content of toxic components in the exhaust gas. On considered cars set the fuel vapor recovery system (EVAP) and crankcase ventilation (PCV). The system controlled crankcase ventilation (PCV) To eliminate leakage of unburned hydrocarbons into the atmosphere the engine completely sealed. Gases and oil vapors formed in said housing, are fed into the intake manifold and burned in the cylinders with the fuel. Gases are removed from the housing by the pressure difference in the intake manifold and the crankcase (crankcase pressure above). PCV Driving Time System of catching of fuel evaporations (EVAP) EVAP system is designed to reduce the emission of unburned hydrocarbons. Fuel filler cap is tightly closed. The coal absorber collected fuel vapors generated in the tank at the time of parking of a vehicle, and are held therein as long as the alarm control unit starts scavenging absorber. During purging fuel vapors are fed through the purge valve in the inlet conduit where it is mixed with the working mixture and further combusted in a conventional manner in the combustion chambers. To ensure the normal operation of the engine at idle and during the warm-up control unit keeps the valve closed. This prevents the ingress of unburned fuel in the catalytic converter (at high idle mixture pereobogaschena). After warming up the engine valve starts to open and close, regulating the supply of fuel vapors into the intake tract. Scheme of the EVAP system The catalytic converter and lambda probe To reduce the amount of harmful emissions in the exhaust system is integrated three-functional catalytic converters. The control system has a fuel injection feedback, which includes the lambda probes constantly informing the control unit of the composition of the exhaust gas. Depending on the data obtained, the control unit adjusts the quality of the mixture supplied to the combustion chamber and thus optimizes the combustion conditions. The working surface of the lambda probe is sensitive to changes in the oxygen content in the exhaust gas. Depending on the concentration and the sensor output voltage changes. If the mixture pereobogaschena (oxygen content in the exhaust gas is very low), oxygen sensor transmits signals with low voltage. Tension increases as the lean and increasing the oxygen content in gases. The most efficient converter operates at an optimum air-fuel ratio (14.7 parts air to 1 part of fuel).
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