2003 SSANGYONG MUSSO fuel pressure

M162 ENGINE CONTROLS 1F1-29
FUEL PRESSURE AND INTERNAL LEAKAGE TEST
01 Pressure Tester
02 Pressure Hose
03 Measuring Beaker
Preparation Connection of the Equipment
1. Turn the ignition switch to "OFF" position.
2. Remove the air cleaner cross pipe.
3. Remove the cap on fuel pressure test plug and connect the
pressure hose and pressure tester.
4. Prepare the beaker for measuring the amount of fuel.
Tools Required
103 589 00 21 00 Pressure Tester
119 589 04 63 00 Pressure Hose

1F1-30 M162 ENGINE CONTROLS
Failurecode ItemChecking method
Te s t
stepRequirementSpecified value Possible cause
3.2 - 3.6 bar



Fuel
pressure:in idling speed- When the vacuum isapplied 
Engine:in idling
- Close the valve screw on pressuretester
1.0 Connect the fuel
pressure test plug tothe pressure tester
(refer to the flgure on previous page). 
Fuel pump test
 Fuel pressure
regulator
3.7 - 4.2 bar



Fuel
pressure:in idling speed- When the vacuum isnot applied 
Engine:in idling
- Close the valve screw on pressuretester

2.0 Connect the fuel
pressure test plug tothe pressure tester
(refer to the flgure on previous page). 
Fuel pressure
regulator
> 3.0 bar



Fuel system
internalleakage: 
Engine:stop
3.0 Connect the fuel
pressure test plug tothe pressure tester
(refer to the flgure on previous page). 
The pressure drops
rapidly:non-returnvalve in fuel pump
> 2.5 bar

After 30 minutes from
engine stop 
The pressure drops
slowly: - Injector test- Fuel pressure regulator
- O-ring

M162 ENGINE CONTROLS 1F1-31
FUEL PUMP TEST Preparation
1 ECU
2 Test Coupling(No.1-60)
3 Test Coupling(No.61-120)
4 Stop Watch
5 Measuring Beaker
Connection of the Equipment
1. Turn the ignition switch to "OFF" position. 2. Connect the test box to the ECU. 0 3 Test Box
04 ECU Test Cable
Tools Required
103 589 00 21 00 Pressure Tester 210 589 00 99 00 Adaptor Line
129 589 00 21 00 Test Box
210 589 08 63 00 Ecu Test Cable

1F1-46 M162 ENGINE CONTROLS1 Vacuum Hose
2 Circlip
3 Fuel Pressure Regulator
FUEL PRESSURE REGULATOR
4 O-ring ..................................................... replace
5 O-ring ..................................................... replace

M162 ENGINE CONTROLS 1F1-47
3. Disconnect the vacuum hose.
4. Disconnect the circlip and remove the fuel pressureregulator.
5. Apply the oil to O-ring lightly and then replace it.
6. Installation should follow the removal procedure in the reverse order.
7. Check for fuel pressure and internal leaks by operating the engine.
2. Discharge the pressure in fuel supply system by pressing
the service valve.
Removal & Installation Procedure
1. Remove the fuel pressure test connector.

1F1-48 M162 ENGINE CONTROLSA . Valves Closed
B. Valves Opened
The pressure difference between the fuel pressure and the intake manifold is about 3.8 bars during the full load. The spring chamber(9) is connected to the intake manifold with the vacuum hose at the intake pipe connection(7). Thenegative pressure generated in the intake manifold activates the diaphragm, and thus the fuel pressure gets reduced to the rate of the operating extent of the diaphragm by the intakemanifold's negative pressure.
Consequently, the fuel pressure in the fuel distributor changes by the intake manifold's negative pressure, and the injector'sfuel pressure gets reduced independently to the throttle valve'sposition. Thus, the fuel injection volume can only be determined according to the injector's injecting duration. 2. Fuel return line
3. Valve
5. Diaphragm
6. Compression Spring
8. Fuel Chamber
9. Spring Chamber
1. Fuel Pressure Regulator
2. Intake Manifold
3. Fuel Return(to fuel tank)
4. Fuel Supply(form fuel pump)
5. Fuel Pressure(approx. 3.8 bars)
6. Intake Manifold Negative Pressure(0 bar)
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 tothe intake manifold pressure. This operating pressure cannotbe changed, and the fuel injection volume will be only determined by the injection time. Over supplied fuel returns to the fuel tank through the return line. There is no negative pressure applied to the spring chamber(9) during the full load, and it is separated from the fuel chamber(8)by the diaphragm(5). When the fuel pressure goes up, the diaphragm forces the compression spring(6) in the direction of compression . At thismoment, the valve(3) sticks to the diaphragm by the fuelpressure, and the fuel return line(2) opens. The fuel over supplied returns to the fuel tank through the return line.

M162 ENGINE CONTROLS 1F1-49
The pressure difference between the fuel pressure and the intake manifold is approx. 3.2 bars during idling. 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)
A . Fuel pressure
B. Intake Manifold Negative Pressure
LL. Idling
TL. Partial load
V L . Full load

M162 ENGINE CONTROLS 1F1-51
Removal & Installation Procedure
1. Discharge the fuel pressure from the fuel pressure testconnector.
2. Disconnect the battery ground cable.
3. Disconnect the vacuum hose from the fuel pressure regulator.
4. Remove the cable guide.
5. Remove the fuel return and supply line.
Notice
For removal, cover around parts with cloths not to be
stained by fuel.
In case of checking the injector only, do not remove the
fuel return and supply line.
Installation Notice
6. Remove the six injector connectors.
7. Remove the two left and two right bolts and one center bolt of the fuel distributor assembly from the intake manifold. Installation Notice
Tightening Torque 25 - 30 Nm
Tightening Torque 22.5 - 27.5 Nm