User manual MITSUBISHI ENGINE AND EMISSION CONTROL SERVICE SPECIFICATIONS

[. . . ] <4G6> (1) Loosen the adjusting nut, and then move the lever to throttle fully-closed position. (2) Tighten the adjusting nut until the lever start to move, turn back one turn, and then tighten the lock nut to the specified torque. <4G9> (1) Loosen the adjusting bolt or adjusting nut to release the cable. [. . . ] The blow-by gas inside the crankcase is drawn into the intake manifold through the positive crankcase ventilation (PCV) valve. The PCV valve lifts the plunger according to the intake manifold vacuum so as to regulate the flow of blow-by gas properly. In other words, the blow-by gas flow is regulated during low load engine operation to maintain engine stability, while the flow is increased during high load operation to improve the ventilation performance. SYSTEM DIAGRAM Ventilation hose PCV valve Breather hose COMPONENT LOCATION PCV valve <4G9> PCV valve <4G6> ENGINE AND EMISSION CONTROL - Emission Control System 17-11 POSITIVE CRANKCASE VENTILATION SYSTEM CHECK 1. Place a finger at the opening of the PCV valve and check that vacuum of the intake manifold is felt. PCV valve NOTE At this moment, the plunger in the PCV valve moves back and forth. If vacuum is not felt, clean the PCV valve or replace it. PCV VALVE CHECK 1. Insert a thin rod into the PCV valve from the side shown in the illustration (rocker cover installation side), and move the rod back and forth to check that the plunger moves. In this case, clean or replace the PCV valve. 17-12 ENGINE AND EMISSION CONTROL - Emission Control System EVAPORATIVE EMISSION CONTROL SYSTEM GENERAL INFORMATION The evaporative emission control system prevents fuel vapours generated in the fuel tank from escaping into the atmosphere. Fuel vapours from the fuel tank flow through the fuel tank pressure control valve and vapour pipe/hose to be stored temporarily in the canister. When driving the vehicle, fuel vapours stored in the canister flow through the purge solenoid and purge port and go into the intake manifold to be sent to the combustion chamber. When the engine coolant temperature is low or when the intake air quantity is small (when the engine is at idle, for example), the engine control unit turns the purge solenoid off to shut off the fuel vapour flow to the intake manifold. This does not only insure the driveability when the engine is cold or running under low load but also stabilize the emission level. SYSTEM DIAGRAM Throttle body Engine-ECU Canister From fuel tank Purge control solenoid valve (ON: Open) Control relay Air flow sensor Engine coolant temperature sensor Intake air temperature sensor Barometric pressure sensor COMPONENT LOCATION Purge control solenoid valve <4G9> Purge control solenoid valve<4G6> ENGINE AND EMISSION CONTROL <4G9> Vacuum hose (red stripe) Emission Control System 17-13 PURGE CONTROL SYSTEM CHECK 1. Disconnect the vacuum hose (red stripe) from the throttle body <4G9>, intake manifold <4G6>, and connect it to a hand vacuum pump. When the engine is cold or hot, apply a vacuum of 53 kPa, and check the condition of the vacuum. When engine is cold (Engine coolant temperature: 40_C or less) Engine condition Normal condition Vacuum is maintained At idle 3, 000 r/min Plug <4G6> Plug Vacuum hose (red stripe) When engine is hot (Engine coolant temperature: 80_C or higher) Engine condition At idle 3, 000 r/min (fore approximately 3 minutes after the engine is started. ) <4G9> Normal condition Vacuum is maintained Vacuum will leak. PURGE PORT VACUUM CHECK 1. Disconnect the vacuum hose (red stripe) from the throttle body <4G9>, intake manifold <4G6> purge vacuum nipple and connect a hand vacuum pump to the nipple. Vacuum hose (red stripe) <4G6> Vacuum hose (red stripe) 17-14 Vacuum ENGINE AND EMISSION CONTROL - Emission Control System 2. Check that the operation sound of the stepper motor can be heard from the EGR valve when the ignition switch is turned to ON (without starting the engine). [. . . ] (2) Connect terminal No. 3 and terminal No. 4 to negative ( - ) terminal of the power supply. (3) Connect terminal No. 3 and terminal No. 6 to negative ( - ) terminal of the power supply. (4) Connect terminal No. 1 and terminal No. 6 to negative ( - ) terminal of the power supply. [. . . ]