egr valve and turbo charger actuator control vacuum circuit

42
04
EGR VALVE AND TURBO CHARGER ACTUATOR CONTROL VACUUM
CIRCUIT
Vacuum Modulator
The biggest difference between the vacuum circuit and layout of the HUBER EGR system after K2004 has been
introduced is the location of the vacuum modulator for EGR valve control and the function of the other modulator. In
case of EGR equipped vehicle (IDI Engine), it performs the role of controlling the PLA of injection pump whereas, in
DI engine, it controls the turbo charger actuator.
DI engine vacuum modulator
1. Turbo charger booster vacuum modulator
D20DT
To EGR valve
From vacuum pump
2. EGR valve vacuum modulator
To Turbo Charger Actuator (Gray)
To EGR Valve (Black)
To turbo charger
actuator
Vacuum pump
D27DT
From vacuum
pump
To EGR Valve
To turbo charger
actuator
Vacuum pump
1. Vacuum modulator for EGR valve control
2. Vacuum modulator for injection pump PLA control
EXHAUST SYSTEM
KYRON SM - 2005.09
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
43
Vacuum Modulator and Vacuum Hose
Below figures illustrate vacuum hoses and related parts of EGR or turbo where wrong or poor connection of vacuum
hose would display condition of engine irregularity and defect diagnostic codes on the scan tool.
ASSY
Related with EGR valve
GENERAL
04
HOUSING
From vacuum pump
COOLING
LUB
EXHAUST I N T A K E
EGR valve
FUEL
Vacuum modulator for
EGR valve control
SENSOR
CONTROL
Related with turbo charger actuator
Turbo charger pressure valve
Vacuum modulator for turbo
charger booster control
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
From vacuum pump
EXHAUST SYSTEM
KYRON SM - 2005.09
44
04
EGR System Diagram
Intercooler
Exhaust
manifold
Intake
manifold
EGR
valve
Regulated
vacuum
pressure
Modulator
Vacuum
pump
Duty
control
Feedback EGR
(Air Mass)
ECU
Improved target EGR
Air intake
signal (for
EGR feedback
control)
Turbo charger
Pedal RPM
signal signal
EGR valve
EGR valve recirculates some of exhaust gases to intake system to reduce toxic NOx from engine according to ECU
signals.
1. EGR valve opening point : -270 mmHg
EGR modulator
According to ECU signals, the vacuum modulator drives EGR valve by controlling vacuum pressure that is generated
by vacuum pump with PWM type controls.
EXHAUST SYSTEM
KYRON SM - 2005.09
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
04
45
GENERAL
Operation Principle of Vacuum Modulator
ASSY
Vacuum
pump
HOUSING
Output vacuum
ATM
EXHAUST I N T A K E
Plunger
COOLING
LUB
Connector
Vacuum
control
FUEL
Diaphragm
Seat assembly
Spring
Atmospheric pressure
SENSOR
CONTROL
Plunger
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.
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
EXHAUST SYSTEM
KYRON SM - 2005.09
46
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 vacuum (-mmHg)
Output characteristics
EXHAUST SYSTEM
KYRON SM - 2005.09
Up
Down
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
04
47
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)
HOUSING
6. Coolant temperature is within a specified range. (EGR OFF under high or low temperature)
ASSY
GENERAL
Operating conditions
EXHAUST I N T A K E
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
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.
FUEL
Shut-off conditions
COOLING
LUB
4) Intake air temperature (HFM): Decreases when over 60°C
1. Engine rpm: over 2,950 rpm
2. Vehicle speed: over 105 km/h
CONTROL
3. Coolant temperature: over 100°C or below 10°C
SENSOR
4. Idle period: over 50 seconds
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
EXHAUST SYSTEM
KYRON SM - 2005.09
48
04
EGR Valve and Pipe
- Removal and Installation
1. Remove the vacuum hose from the EGR valve.
D20DT
D27DT
2. Unscrew the bolts and remove the EGR valve (2), EGR
valve #1 pipe (1) and gasket.
Installation Notice
Tightening torque
25 ± 2.5 Nm
D20DT
D27DT
M6 Bolt: 10 ± 1.0 Nm
EXHAUST SYSTEM
KYRON SM - 2005.09
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
04
49
GENERAL
3. Remove the EGR valve #1 pipe, #2 pipe, #3 pipe and
gaskets from the engine.
Installation Notice
25 ± 2.5 Nm
D27DT
EXHAUST I N T A K E
HOUSING
D20DT
ASSY
Tightening torque
LUB
4. Install in the reverse order of removal.
COOLING
NOTICE
• Make sure to observe the specified tightening
torques.
• Never reuse the EGR #1 pipe (intake) and #3 pipe
(exhaust) once removed (only D27DT).
D27DT
EGR #3 pipe (RH)
EGR #3 pipe (RH)
EGR #1 pipe (LH)
EGR center pipe
SENSOR
EGR center pipe
CONTROL
D20DT
FUEL
• Replace the gaskets with new ones.
EGR #1 pipe (LH)
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
EXHAUST SYSTEM
KYRON SM - 2005.09
50
04
Vacuum Modulator
- Removal and Installation
1. Remove the vacuum hose from the vacuum modulator.
D20DT
D27DT
2. Remove the vacuum modulator from the bracket.
Installation Notice
Tightening torque
10 ± 1.0 Nm
3. Install in the reverse order of removal.
NOTICE
• Make sure that the vacuum hoses are connected
to correct locations.
D20DT
EXHAUST SYSTEM
KYRON SM - 2005.09
D27DT
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN