42 04 VACUUM MODULATOR COMPOSITION Layout Turbocharger actuator EGR valve Vacuum pump hose Vacuum pump Turbocharger vacuum modulator EGR vacuum modulator Vacuum Modulator for VGT Turbocharger Actuator Control Vacuum Modulator for EGR Valve IP internal fuse (RH) No.63-7.5A No. 95 IP internal fuse (RH) No.63-7.5A No. 96
04 43 REMOVAL AND INSTALLATION OF EGR VALVE EGR Valve and Pipe 1. Remove the inlet hose to the intake manifold and disconnect the vacuum hose of the EGR valve. Inlet hose to Intake Manifold Vacuum Hose to EGR Valve 2. Remove the mounting bolt/nut to remove the left pipe of the EGR valve and unscrew four hexagon bolts to remove the EGR valve assembly. Tightening torque (bolt) 10 ± 1.0 Nm EGR Valve Pipe (LH) Tightening torque 6 ~ 7 Nm Tightening torque (bolt) 10 ± 1.0 Nm 3. Remove the right pipe of the EGR valve and remove the center pipe. EGR Valve Assembly Tightening torque (hexagon bolt) 10 ± 1.0 Nm SENSOR CONTROL FUEL COOLING LUB EXHAUST INTAKE HOUSING ASSY GENERAL EGR Valve Pipe (RH) Tightening torque (bolt) 10 ± 1.0 Nm EGR Valve Pipe (Center) Tightening torque (M8 X 30) 25 ± 2.5 Nm Tightening torque (nut) 35 ± 3.5 Nm Tightening torque (M8 X 25) 25 ± 2.5 Nm
44 04 4. Install in the reverse order of removal. NOTICE 1. Observe the tightening torque of the bolts and nuts when installing pipes. 2. Replace the gaskets of the pipes with new ones. The protruding side should face to pressurized section. EGR RH Pipe and Gasket Center pipe bolt (2 EA) (M6 X 16: 10 ± 1.0 Nm) EGR LH Pipe and Gasket Intake pipe bolt (4 EA) (M6 X 16: 10 ± 1.0 Nm) Exhaust manifold nut (2 EA) (M8: 35 ± 3.5 Nm) * M8 mounting nut should be replaced with new one. EGR valve Center Pipe Center pipe upper bolt (2 EA) (M8 X 25: 25 ± 2.5 Nm) EGR Valve EGr valve mounting bolt (4 EA) (M6 X 25: 10 ± 1.0 Nm) Center pipe lower bolt (2 EA) (M8 X 25: 25 ± 2.5 Nm) LH pipe mounting bolt (2 EA) (M6 X 16: 10 ± 1.0 Nm)
04 45 Inspection for EGR System If the EGR system is malfunctioning, the engine power may be decreased or the exhaust gas may be increased. If these happen, troubleshoot the system according to the following procedures. 1. Inspection for EGR vacuum system Check the EGR vacuum system (engine vacuum pump - vacuum modulator for controlling EGR valve - EGR valve) for malfunction. Specifically, check the vacuum hose, connections, kinked hose and leaks due to interference with surrounding components. Also check the EGR vacuum modulator's wiring connector. Make sure that the vacuum system source functions properly by checking the engine vacuum pump for leakage. Vacuum modulator for turbocharger actuator EGR valve Vacuum modulator for EGR valve 2. EGR related DTC check using SCAN-100 Connect the SCAN-100 to the CAN module and check if there is any DTC related to EGR. If DTC is appeared, it may be due to the vacuum system. Therefore, check the EGR system again. Main vacuum when idling: 690 mmhg Brake booster IWE locking hub SENSOR CONTROL FUEL COOLING LUB EXHAUST INTAKE HOUSING ASSY GENERAL DTC Related to EGR System P0400 P1405 P1406 Faulty EGR valve control Short circuit to EGR vacuum modulator (GND) Short circuit to EGR vacuum modulator (B+) All DTCs are related to EGR valve vacuum modulator. Therefore, check the power supply and ground condition by performing the following electrical check for EGR valve vacuum modulator.
46 04 3. Electrical check for EGR valve vacuum modulator The EGR valve vacuum modulator is supplied with power from the main relay and fuse No. 63 (7.5 A) in the interior fuse box which is located in the instrument panel (RH). Therefore, those relays and fuses should be checked first. The vacuum modulator for the VGT turbocharger actuator is installed on the top of the vacuum modulator for EGR valve. Both are supplied with the same power and controlled (duty cycle) by engine ECU. The following is the procedure for checking the power supplied to the vacuum modulator. IP Interior Fuse Box (Passenger Side) Vacuum Modulator main relay VGT & EGR vacuum modulators, HFM Vacuum modulator for VGT turbocharger actuator Vacuum modulator for EGR valve HP pumpimv Hazard warning lamp Connector Connector Installtion of multimeter Terminal No. 1 IP interior fuse (RH) No.63-7.5A No. 96
04 47 4. EGR valve check If there is no problem found so far, check the EGR valve as a unit. The EGR valve is working as a passage for exhaust gas. It may not operate due to the contamination by the carbon or other foreign materials. Check the unit according to the following procedures. 1. Remove the intake inlet hose. 2. Connect the vacuum tester to EGR valve. 3. Check if EGR valve starts to open when the vacuum gauge indicates approx. 220 ~ 250 mmhg. 4. Check the conditions of EGR valve. SENSOR CONTROL FUEL COOLING LUB EXHAUST INTAKE HOUSING ASSY GENERAL If the valve is severely contaminated, completely wipe it out with soft cloth. Be careful not to damage it.
48 04 REMOVAL AND INSTALLATION OF VACUUM MODULATOR ASSEMBLY Removal and Installation 1. Separate the vacuum hose to EGR valve (1), the vacuum hose to turbocharger (2) and the vacuum hose to vacuum pump (3) in turn. EGR valve vacuum hose Vacuum pump hose Vacuum hose for turbocharger actuator Brake booster IWE locking hub 2. Disconnect the vacuum modulator connectors to turbocharger (A) and EGR valve (B). 3. Unscrew the mounting bolts and remove the vacuum modulators. Tightening torque 10 ± 1.0 Nm
04 49 4. Unscrew the mounting bolts and remove the vacuum modulator bracket. GENERAL Vacuum modulator Components Bracket Port to VGT turbocharger actuator 5. Install in the reverse order of removal. Vacuum modulator for VGT turbocharger actuator Port to vacuum pump SENSOR CONTROL FUEL COOLING LUB EXHAUST INTAKE HOUSING ASSY IP internal fuse (RH) No.63-7.5A No. 95 Port to EGR valve IP internal fuse (RH) No.63-7.5A No. 96 Vacuum modulator for EGR valve
50 04 ELECTRICAL CIRCUIT RELATED TO VACUUM MODULATOR Main relay Vacuum modulator for VGT turbocharger actuator Vacuum modulator for EGR valve Engine extension wiring IP Fuse Box (Passenger Side) Engine Main Relay & Fuse No. 63 Engine main relay Fuse No. 63 (7.5A) Fuse No. 63 (7.5A)
04 51 Operation Principle of Vacuum Modulator Vacuum control Atmospheric pressure Vacuum pump Output vacuum ATM Plunger Connector Diaphragm Seat assembly Spring Plunger SENSOR CONTROL FUEL COOLING LUB EXHAUST INTAKE HOUSING ASSY GENERAL Air flow During duty increase (B) During duty reduction (C) Vacuum is controlled according to relationship between chamber pressure (I) in rolling nipple cover and magnetic force (II) in plunger. According to ECU signals, the solenoid valve controls the vacuum pressure that is generated by vacuum pump (-900 ± 20 mbar) with PWM type control and drives the mechanical EGR valve and turbo charger.
52 04 Operating principle: Balance between original vacuum pressure and magnetic forcs (see aboe figure) 1. Normal state (Fig. A): Original vacuum and seat section, 3 stoppers keep sealing 2. Duty up state (Fig. B): Original vacuum pressure is connected to inside of diaphragm chamber 3. Duty down state (Fig. C): Increased diaphragm chamber pressure is connected to atmosphere to compensate the pressure. Floating plunger DUTY 50% Stroke (mm) Max. Distance 1mm Output C/V Operating principles when duty is applied from 0 to 50 % Vacuum consumption: Compared to 50 % of duty, ON/OFF periods are most unstable and vacuum consumption is most high. Flowing volume Output characteristics Output vacuum (-mmhg) Up Down
04 53 Operating conditions 1. Engine is running 2. Engine RPM is within a specified range. (EGR OFF under high RPM range) 3. Engine torque is within a specified range. (EGR OFF under high torque range) 4. Vehicle speed is within a specified range. (EGR OFF under high speed range) 5. Atmospheric pressure is within a specified range. (EGR OFF under high altitude and low atmospheric pressure) 6. Coolant temperature is within a specified range. (EGR OFF under high or low temperature) 7. EGR OFF under extended period of idling. Control logic 1. Main map: EGR volume is controlled based on intake air volume 2. Auxiliary map 1) Coolant temperature (Coolant temperature sensor) 2) Engine rpm (Crankshaft position sensor) 3) Engine load (TPS): Detection of sharp acceleration 4) Intake air temperature (HFM): Decreases when over 60 C 5) Atmospheric pressure (Barometric sensor): Compensation of altitude 3. Compensation value of auxiliary map will be increased/decreased based on main map then ECU calculates EGR volume finally to regulate the vacuum duty that applies to the vacuum modulator to control EGR valve openings. Shut-off conditions 1. Engine rpm: over 2,950 rpm 2. Vehicle speed: over 105 km/h 3. Coolant temperature: over 100 C or below 10 C 4. Idle period: over 50 seconds SENSOR CONTROL FUEL COOLING LUB EXHAUST INTAKE HOUSING ASSY GENERAL