Page 707 of 1463
1F2-58 M161 ENGINE CONTROLS
FUEL PUMP
Requirements for Fuel Pump
ItemSpecified ValueItemSpecified Value
System pressure
3.8 bar
Minimum delivery at 8V 30 Litre/Hr
Maximum pressure
8.5 bar (12 V)
Minimum amount
of fuel supply
114 Liter/Hr (12 V, 3.8 bar, -
30 ~ +70°C)
Minimum pressure5.0 bar (12 V)
Maximum allowable current 7.5 A
Nominal voltage
12 V
Ambient temperature
-30 ~ +70°C
1 Reservoir Tank
2 Fuel Sensor (float/arm)
3 Resistance
4 Wiring Connector
5 Fuel Supply Pipe
7 Float
10 Flange and Harness Assembly
11 Fuel Pump
12 Spring
13 Thermister Housing
14 Thermister
15 Resistor Card and Wiper
16 Float Arm
Operating voltage 8 V
Maximum amount
of fuel supply165 Liter/Hr (12V, 3.8 bar,
-30 ~ +70°C)
Page 708 of 1463
M161 ENGINE CONTROLS 1F2-59
1
2
3
4
1 Fuel Pump Connector Wiring
2 Fuel Return Pipe
3 Fuel Supply Pipe
4 Bolts5 Fuel Return Pipe
6 Fuel Supply Pipe
7 Float
8 Ground Stud (Sender "-")
COLOR
Pump "+"
Thermister "+"
Ground
Sender Unit "+"USE Harness Location & Connector
A
B
C
D
2.0 BR
0.5 W
2.0 B
0.5 RY
Page 709 of 1463
1F2-60 M161 ENGINE CONTROLS
Tools Required
661 589 00 46 00 Cap Remover
Removal & Installation Procedure
1. Disconnect the negative battery cable.
2. Disconnect the harness connector (1).
3. Disconnect the fuel supply (6) and return (5) pipes.
4. Using a special tool, Unscrew the eight fuel retaining bolts
and remove the pump from fuel tank.
Notice
Check the condition of the seal and replace if necessary.
Drain the fuel before removing the pump.
Page 710 of 1463
M161 ENGINE CONTROLS 1F2-61
Notice
Replace the fuel pump relay if the measured value is over
9A. Notice
Check the fuel filter and fuel line when the fuel delivery is
not within specified value.
Measure the Current Consumption of Fuel Pump
1. Remove the fuel pump relay from fuse and relay box in
trunk, and turn the ignition switch to "ON" position.
2. Using a multi-tester, measure the current consumption by
connecting the terminal No.1 and No.3 of pump.
Measure the Fuel Delivery From the Fuel Pump
1. Disconnect the return pipe from fuel distributor and insert
the appropriate hose into it.
2 . Place the hose end into the beaker with the minimum capacity
of 1Liter.
3. Turn the ignition switch to "ON" position.
4. Connect the terminal No.33 and No.5 of ECU with a service
wire.
5. Measure the fuel delivery from the fuel pump.
1Liter/max.35sec. Specifed Value
5 - 9A Specifed Value
Page 730 of 1463

SECTION 1F3
OM600 ENGINE CONTROLS
Specifications . . . . . . . . . . . . . . . . . . . . . . . 1F3-1
Fastener Tightening Specifications . . . . . . . . 1F3-1
Maintenance and Repair . . . . . . . . . . . . . . 1F3-2
On-Vehicle Service . . . . . . . . . . . . . . . . . . . . 1F3-2
Fuel System . . . . . . . . . . . . . . . . . . . . . . . . . 1F3-2
Fuel Injection Pump Coding . . . . . . . . . . . . . 1F3-3
Fuel Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . 1F3-4
Vacuum Control System Test . . . . . . . . . . . . 1F3-5
Vacuum Pump(Sectional View) . . . . . . . . . . 1F3-10
Vacuum Pump Test . . . . . . . . . . . . . . . . . . . 1F3-11
Vacuum Pump . . . . . . . . . . . . . . . . . . . . . . 1F3-13
Vacuum Unit Replacement . . . . . . . . . . . . . 1F3-15Idle Speed Adjustment . . . . . . . . . . . . . . . . 1F3-16
Fuel Pump Test . . . . . . . . . . . . . . . . . . . . . . 1F3-18
Fuel Pump . . . . . . . . . . . . . . . . . . . . . . . . . 1F3-21
Injection Nozzle Test . . . . . . . . . . . . . . . . . . 1F3-22
Injection Nozzles . . . . . . . . . . . . . . . . . . . . . 1F3-25
Injection Nozzle Repair . . . . . . . . . . . . . . . . 1F3-27
Removal and Installation of
Injection Timing Device . . . . . . . . . . . . . . 1F3-30
Injection Timing Device . . . . . . . . . . . . . . . . 1F3-35
Start of Delivery Test
(Position Sensor, RIV Method) . . . . . . . . . 1F3-37
Fuel Injection Pump . . . . . . . . . . . . . . . . . . 1F3-46
TABLE OF CONTENTS
Caution: Disconnect the negative battery cable before removing or installing any electrical unit or when a
tool or equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable
will help prevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwise
noted.
SPECIFICATIONS
FASTENER TIGHTENING SPECIFICATIONS
Application
Fuel Tank Mounting Nut
Fuel Pump Pressure Line
Fuel Injection Nozzle
Fuel Injection Pipe
Nozzle Tensioning Nut
Screw Plug
Left-Hand Thread BoltN·m
28 - 47
13
35 - 40
18
80
30
46
Page 731 of 1463
1F3-2 OM600 ENGINE CONTROLS
FUEL SYSTEM
1 Fuel Injection Pump
2 Fuel Feed Pump
3 Overflow Valve
4 Injection Nozzle
5 Pre-filter6 Fuel Return Hose
7 Injection Line
8 Fuel Tank
9 Fuel Filter
10 Choke Orifice
MAINTENANCE AND REPAIR
ON-VEHICLE SERVICE
Page 732 of 1463
OM600 ENGINE CONTROLS 1F3-3
FUEL INJECTION PUMP CODING
Model Code
PES 4M 55C 320 RS 167
PES 5M 55C 320 RS 168
Fuel Injection Pump Code
Example)PES 5M 55C 320 RS 168
P Pump
E Self-Driven
S End Flange Mounting
5 Number of Cylinders (5EA)
M Pump Size
55 Element Diameter
C Modification Letter
320 Assembly Number
R Direction of Rotation (clockwise)
S188 Special Version
RSF Governor
R Governor
S Coil Spring
F Drive Governor
Component Location
1. Fuel Injection Pump
2. Vacuum Unit (Stop Unit)
3. Control Lever
4. PLA Vacuum Unit (Idle Speed Adjustment)
5. Governor
6. Fuel Pump
OM661 LA Engine
OM662 LA Engine
Page 734 of 1463
OM600 ENGINE CONTROLS 1F3-5
VACUUM CONTROL SYSTEM TEST
2 Engine Cut-Off Valve (Ignition Key Switch)
3 Auto-locking Hub Solenoid Valve
4 Engine Stop Valve Unit
5 PLA Vacuum Unit (Idle Speed Adjustment)
6 Engine
7 Vacuum Pump8 30° Thermovalve
9 Fuel Injection Pump
10 Filter with Restriction
11 Check Valve
12 Modulating Pressure Line (Automatic T/M)
Test Data
Idle Speed Increase
Permissible Pressure Drop of SystemAt least 100 rpm at approx. 500mbr
400 - 500mbar approx. 1 min.