SsangYong Stavic / SsangYong Rodius (2005 year). Manual - part 49

1F-37

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EFFECTIVE DATE

AFFECTED VIN

ENGINE CONTROLS

M162 GSL ENG SM - 2005.7

Fuel Pressure Test

Tools Required

A9922 0012A (103 589 00 21 00)

Fuel Pressure Gauge

1. Turn the ignition switch to “OFF” position.

2. Remove the fuel pressure test connector.

3. Connect the fuel pressure gauge to the fuel pressure

test connector.

4. Test the fuel pressure at idling by operating the engine

using the fuel pressure gauge A9922 0012A (103 589
00 21 00).

Internal Leakage Test

1. Connect thefuel pressure gauge A9922 0012A (103 589

00 21 00) to the fuel pressure test connector.

2. Stop the engine for approximately 30 minutes and then

check the fuel pressure changes.

5. Replace the pressure regulator diaphragm if out of the

specification.

3. If there is no change in fuel pressure and maintain the

following pressure over 30 minutes, it is normal.

Vacuum hose connected (bar)

Vacuum hose disconnected (bar)

3.2 ~ 3.6

3.7 ~ 4.2

Fuel pressure (bar)

Pressure Change

Fuel pressure drops

slowly

Fuel pressure drops

rapidly

• Fuel leakage at the

injector

• Faulty fuel pressure

regulator’s
diaphragm and O-ring

• Faulty check valve in

the fuel pump

1F-38

CHANGED BY

EFFECTIVE DATE

AFFECTED VIN

ENGINE CONTROLS

M162 GSL ENG SM - 2005.7

FUEL PRESSURE REGULATOR

2. Fuel return line

3. Valve

5. Diaphragm

6. Compression spring

1. Vacuum hose

2. Circlip

3. Fuel pressure regulator

4. O-ring

5. O-ring

8. Fuel chamber

9. Spring chamber

A. Valves closed

B. Valves opened

Function of the Fuel Pressure Regulator

The fuel pressure regulator maintains the fuel pressure in the
fuel line with the pressure of 3.2 bars to 3.8 bars according to
the intake manifold pressure. This operating pressure cannot
be changed, and the fuel injection volume will be only deter-
mined by the injection time.

Over supplied fuel returns to the fuel tank through the return line.

<Operating at full load>

There is no negative pressure applied to the spring chamber
(9) during the full load, and it is separated from the fuel cham-
ber (8) by the diaphragm (5).

When the fuel pressure goes up, the diaphragm forces the
compression spring (6) in the direction of compression. At
this moment, the valve (3) sticks to the diaphragm by the fuel
pressure, and the fuel return line (2) opens. The fuel over sup-
plied returns to the fuel tank through the return line.

1F-39

CHANGED BY

EFFECTIVE DATE

AFFECTED VIN

ENGINE CONTROLS

M162 GSL ENG SM - 2005.7

1. Fuel pressure regulator

2. Intake manifold

3. Fuel return (to fuel tank)

4. Fuel supply (from fuel pump)

5. Fuel paressure (approx. 3.8 bars)

6. Intake manifold negative pressure (0 bar)

Consequently, the fuel pressure in the fuel distributor
changes by the intake manifold’s negative pressure, and
the injector’s fuel pressure gets reduced independently
to the throttle valve’s position. Thus, the fuel injection
volume can only be determined according to the injector’s
injecting duration.

The pressure difference between the fuel pressure and
the intake manifold is approx. 3.2 bars during idling.

<Operating at Idle and partial load>

The spring chamber (9) is connected to the intake mani-
fold with the vacuum hose at the intake pipe connection
(7). The negative pressure generated in the intake mani-
fold activates the diaphragm, and thus the fuel pressure
gets reduced to the rate of the operating extent of the
diaphragm by the intake manifold’s negative pressure.

1. Fuel pressure regulator

2. Intake manifold

3. Fuel return (to fuel tank)

4. Fuel supply (from fuel pump)

7. Fuel pressure (approx. 3.2 bars)

8. Intake manifold negative pressure (0.6 bars)

<Fuel Pressure Diagram>

A. Fuel pressure

B. Intake manifold negative pressure

LL. Idling

TL. Partial load

VL. Full load

The pressure difference between the fuel pressure and
the intake manifold is about 3.8 bars during the full load.

1F-40

CHANGED BY

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AFFECTED VIN

ENGINE CONTROLS

M162 GSL ENG SM - 2005.7

THROTTLE VALVE ACTUATOR

INDUCTION SYSTEM

The throttle actuator is actuated by the Engine Control
Module(ECM) according to the position of the accelera-
tor pedal position.

It has two potentiometers which signal the position of the
throttle valve to the ECM to enable it to recognize the
various engine load states.

Ignition “OFF”

In the de-energized states the throttle valve position is
determined to be spring capsule.

Ignition “ON”

When the ignition S/W on the servo motor in the throttle
actuator is operated by the ECM. The throttle valve adopts
a position in line with the coolant temperature.

Closed Position

In the closed throttle position, the servo motor controls
engine speed by operating the throttle valve further (greater
mixture) or closing it further (reduced mixture), depend-
ing on coolant temperature and engine load. When this is
done, the throttle valve can be closed further by the servo
motor overcoming the force of the spring capsule (me-
chanical end stop). If the actuator is deenergized, the
throttle valve is resting against the spring capsule.

Consequently, the throttle valve opening is a constant 10
~ 12° approximately.

At no load, this produces an engine speed of about 1,800 rpm

Driving

When driving (part/full throttle), the servo motor controls
the throttle valve in line with the various load states and
according to the input signals from the pedal value sen-
sor according to the input signals from the pedal value
sensor according to the position of the accelerator pedal.

The function of the EA (electronic accelerator) in the ECM
determines the opening angle of the throttle valve through
the throttle actuator. Further functions are;

• Idle speed control

• Cruise control

• Reducing engine torque for ASR/ABS operation

• Electronic accelerator emergency running

• Storing faults

• Data transfer through CAN