Cars are equipped with an electronically controlled evaporative emission control system, as shown in Fig.6 and Fig. 258.
Fuel vapor from fuel tank enters into the intake manifold through a carbon canister charged with active carbon and a
vacuum solenoid valve. When the engine stops, runs at idle or low speed, the vacuum solenoid valve will be closed under
the control of ECU, therefore enabling the fuel vapor from the fuel tank to be stored in the carbon canister rather than to
be emitted into the atmosphere. When the engine is running at a high speed, ECU will timely open the vacuum solenoid
valve according to the engine’s working condition, enabling the fuel vapor to be absorbed into the intake manifold for
burning with the mixture within the cylinder. So, this system serves to effectively control HC emission without affecting the
engine normal running.
The schematic diagram of the evaporative emission control system is as shown in Fig. 259.
Apply voltage to the terminal 1 and 3 of the battery. Check whether there is a connection between 2 and 4 by using a
multimeter; if not, you shall replace the main relay.
4. Reinstall the EFI main relay and its case cover.
VI. Examination of Vacuum Solenoid Valve (VSV) for
Evaporative Emission (EVAP) Control System
Fig. 258 Schematic diagram of the evaporative emission control system
Vacuum solenid valve for evaporative emission contrd
Positive crankcase valve
Carbon CAnister
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Содержание JL481Q
Страница 1: ......
Страница 9: ...5 Fig 3 Components Assembly Drawing of MR479Q MR479QA Engine ...
Страница 10: ...6 Fig 4 MR479Q MR479QA Engine and Its Power System ...
Страница 11: ...7 Fig 5 Assembly Drawing of Engine and Its Auxiliaries MR479Q MR479QA ...
Страница 12: ...8 Fig 6 Electronic Control Fuel Injection System in Engine MR479Q MR479QA ...
Страница 13: ...9 Fig 7 Front view of Engine JL481Q MR481QA ...
Страница 14: ...10 Fig 8 Sectional elevation of Engine JL481Q MR481QA ...
Страница 15: ...11 Fig 9 Electronic Control Fuel Injection System in Engine JL481Q MR481QA ...
Страница 21: ...17 Fig 13 Exterior Feature of JL481Q Engine Power Me N m Torque Pe Kw ge g kwh Fuel Consumption Ratio ...