Page 504 of 2053

1F2 -- 86 M161 ENGINE CONTROLS
D AEW OO M Y_2000
ENGINE CONTROL MODULE
YAA1F830
The Engine Control Module (ECM), located inside the right side kick panel, is the control center of the fuel injection
system. It constantly looks at the information from various sensors and controls the systems that affect the vehicle’s
performance. Engine rpm and air mass are used to measure the air intake quantity resulting in fuel injection metering.
The ECM also performs the diagnostic functions of the system. It can recognize operational problems, store failure
code(s) which identify the problem areas to aid the technician in making repairs.
There are no serviceable parts in the ECM. The calibrations are stored in the ECM in the Programmable Read Only
Memory (PROM).
The ECM supplies either 5 or 12 volts to power the sensors or switches. This is done through resistance in the ECM
which are so high in value that a test light will not come ON when connected to the circuit. In some cases, even an
ordinary shop voltmeter will not give and accurate reading because its resistance is too low. You must use a digital
voltmeter with a 10 Mohm input impedance to get accurate voltage readings. The ECM controls output circuits such as
the ignition coils, the fuel injectors, the fuel pump relay, the camshaft actuator, the canister purge valve, etc., by con-
trolling the ground circuit.
Page 513 of 2053

M161 ENGINE CONTROLS 1F2 -- 95
D AEW OO M Y_2000
MAINTENANCE AND REPAIR
YAA1F700
ON VEHICLE SERVICE
DISCHARGING THE PRESSURE IN
FUEL SYSTEM
Removal and Installation Procedure
1. Remove the fuel pressure test connector.
Installation Notice
Tightening Torque
25 NSm (18 lb-ft)
YAA1F710
2. Remove the fuel pressure in fuel system by pressing
the service valve with a clean, pointy tool.
Notice:Place a cloth so that the fuel doesn’t stain
around.
3. Installation should follow the removal procedure in
the reverse order.
YAA1F170
FUEL PUMP
Tools Required
661 589 00 46 00 Fuel Tank Cap Wrench
Removal and Installation Procedure
Caution: The fuel system is under pressure. To
avoid fuel spillage and the risk of personal injury or
fire, it is necessary to relieve the fuel system pres -
sure before disconnecting the fuel lines.
1. Relieve the fuel system pressure. Refer to “Discharg-
ing the Pressure in Fuel System” in this section.
2. Disconnect the negative battery cable.
3. Put aside the floor carpet to remove the fuel pump ac-
cess cover.
4. Remove the fuel pump access cover.
5. Remove the fuel pump wiring connectors.
6. Disconnect the fuel supply and return pipes.
7. Remove the fuel pump locking cap band.
Page 516 of 2053

1F2 -- 98 M161 ENGINE CONTROLS
D AEW OO M Y_2000
YAA1F180
14. Turn the roll over valves counterclockwise at an
angle of 90 degrees.
15. Turn the lock ring counterclockwise.
16. Remove and discard the gasket.
17. Installation should follow the removal procedure in
the reverse order.
YAA1F700
FUEL PRESSURE REGULATOR
Removal and Installation Procedure
1. Disconnect the negative battery cable.
2. Remove the fuel pressure test connector.
Installation Notice
Tightening Torque
25 NSm (18 Ib-ft)
YAA1F720
Caution: The fuel system is under pressure. To
avoid fuel spillage and the risk of personal injury or
fire, it is necessary to relieve the fuel system pres -
sure before disconnecting the fuel lines.
3. Relieve the fuel pressure in fuel supply system by
pressing the service valve.
YAA1F730
4. Disconnect the vacuum hose.
5. Disconnect the circlip and remove the fuel pressure
regulator.
6. Apply the oil to O-ring lightly and then replace it.
7. Perform a leak test of the fuel pressure regulator
with the engine off and the ignition on.
8. Installation should follow the removal procedure in
the reverse order.
Page 518 of 2053

1F2 -- 100 M161 ENGINE CONTROLS
D AEW OO M Y_2000
YAA1F770
Notice:Before removal, the fuel rail assembly may be
cleaned with a spray-type cleaner, following package in-
structions. Do not immerse the fuel rails in liquid clean-
ing solvent. Use care in removing the fuel rail assembly
to prevent damage to the electrical connectors and in-
jector spray tips. Prevent dirt and other contaminants
from entering open lines and passages. Fittings should
be capped and holes plugged during service.
Important:If an injector becomes separated from the
rail and remains in the cylinder head, replace the injector
O-ring seals and the retaining clip.
12. Remove the injectors and the fuel rail carefully.
13. Remove the fuel injector retainer clips.
14. Remove the fuel injectors by pulling them down and
out.
15. Discard the fuel injector O-rings.
16. Lubricate the new fuel injector O-rings with engine
oil. Install the new O-rings on the fuel injectors.
17. Perform a leak check of the fuel rail and fuel injec-
tors.
18. Installation should follow the removal procedure in
the reverse order.
YAA1F780
ENGINE COOLANT TEMPERATURE
SENSOR
Removal and Installation Procedure
1. Relieve the coolant system pressure.
2. Disconnect the negative battery cable.
3. Disconnect the engine coolant temperature sensor
connector.
Notice:Take care when handling the engine coolant
temperature sensor. Damage to the sensor will affect
the proper operation of the fuel injection system.
4. Remove the engine coolant temperature sensor
from the pump hosing.
Installation Notice
Tightening Torque
30 NSm (22 Ib-ft)
5. Installation should follow the removal procedure in
the reverse order.
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M161 ENGINE CONTROLS 1F2 -- 103
D AEW OO M Y_2000
KAA1F410
PEDAL POSITION SENSOR
Removal and installation Procedure
1. Disconnect the negative battery cable.
2. Disconnect the pedal position sensor connector.
3. Unscrew the bolts and nut.
Installation Notice
Tightening Torque
6NSm (53 lb-in)
4. Remove the pedal and sensor assembly.
5. Installation should follow the removal procedure in
the reverse order.
YAA1F820
OXYGEN SENSOR
Removal and Installation Procedure
1. Disconnect the negative battery cable.
Notice:The oxygen sensor uses a permanently at-
tached pigtail and connector. This pigtail should not be
removed from the oxygen sensor. Damage or removal
of the pigtail or the connector could affect proper opera-
tion of the oxygen sensor. Do not drop the oxygen sen-
sor.
2. Disconnect the electrical connector.
3. Carefully remove the oxygen sensor from the exhaust
pipe.
Installation Notice
Tightening Torque
55 NSm (41 Ib-ft)
Important:A special anti-seize compound is used on
the oxygen sensor threads. This compound consists of
a liquid graphite and glass beads. The graphitewill burn
away, but the glass beadswill remain, making the sen-
sor easier to remove. New or serviced sensors will al-
ready have the compound applied to the threads. If a
sensor is removed from any engine and is to be rein-
stalled, the threads must have an anti-seize compound
applied before reinstallation.
4. Coat the threads of the oxygen sensor with an anti-
seize compound, if needed.
5. Installation should follow the removal procedure in
the reverse order.
Page 524 of 2053
D AEW OO M Y_2000
SECTION 1G2
M161 ENGINE INTAKE & EXHAUST
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 other -
wise noted.
TABLE OF CONTENTS
Specifications 1G2 -- 2...........................
Fastener Tightening Specifications 1G2 -- 2.........
Maintenance and Repair 1G2 -- 3..................
On-- Vehicle Service 1G2-- 3........................
Air Cleaner 1G2-- 3.............................
Air Intake Shield 1G2-- 5.........................Intake Air Duct 1G2--6..........................
Intake Manifold 1G2--8.........................
Exhaust Manifold 1G2-- 10.......................
Removal and Installation of Exhaust
System 1G2-- 12.............................
Page 526 of 2053
M161 ENGINE INTAKE & EXHAUST 1G2 -- 3
D AEW OO M Y_2000
MAINTENANCE AND REPAIR
ON -- VEHICLE SERVICE
AIR CLEANER
1 Air Cleaner Assembly
2 Element Assembly
3 Insulator4 Air Duct Hose
6 Bolt (M8 x 30 ) 22.5-- 27.5 NSm ...............
Page 536 of 2053

D AEW OO M Y_2000
SECTION 1
ENGINE
SECTION 1A3 (OM600 ENGINE)
GENERAL ENGINE INFORMATION
TABLE OF CONTENTS
Specifications 1A3 -- 1............................
Engine Specifications 1A3-- 1.....................
Sectional View 1A3 -- 3............................
OM662LA Engine 1A3-- 3........................
OM661LA Engine 1A3-- 5........................
Performance Curve 1A3-- 7........................
OM662LA Engine 1A3-- 7........................
OM661LA Engine 1A3-- 8........................
Special Tools 1A3 -- 9.............................Special Tools Table 1A3-- 9.......................
Diagnosis 1A3 -- 10................................
Oil Leak Diagnosis 1A3-- 10.......................
Compression Pressure Test 1A3-- 11..............
Cylinder Pressure Leakage Test 1A3-- 13...........
General Information 1A3 -- 15......................
Cleanliness and Care 1A3 -- 15....................
On-- Engine Service 1A3-- 15......................
SPECIFICATIONS
ENGINE SPECIFICATIONS
ApplicationOM662LAOM661LA
Engine TypeFour -- Stroke DieselFour -- Stroke Diesel
Displacement (CC)28742299
Cylinder (Bore x Stroke)(mm)89 x 92.489 x 92.4
Fuel Injection / Ignition SystemPES 5 M55 C320 RS 168PES 5 M55 C320 RS 167
Compression Ratio22 :122 :1
Number of Cylinders54
Camshaft Valve ArrangementSOHCSOHC
Camshaft Drive TypeChain -- DriveChain-- Drive
Max. Output (ps/rpm)120 / 4000101 / 4000
Max. Torque (kgSm/rpm)25.5 / 400021.5 / 2400
Firing Order1--2--4--5--31--3--4--2
Injection TimingBTDC 18_±10_BTDC 18_±10_
Valve Timing
(t2lift)
IntakeOpen/CloseAT DC 11 . 3 3_/ ABDC 17_AT DC 11 . 3 3_/ ABDC 17_g
(at 2mm lift)ExhaustOpen/CloseBBDC 28_/ BTDC 15.25_BBDC 28_/ BTDC 15.25_
Valve Clearance AdjustmentAutomatic ControlAutomatic Control