1998 DODGE DURANGO Fuel system

Downloaded from www.Manualslib.com manuals search engine CONDITION POSSIBLE CAUSES CORRECTION
3. Worn or incorrectly gapped spark
plugs3. Replace or clean and re-gap spark plugs (Refer to
group 8D, Ignition System)
4. Worn or burned distributor rotor 4. Install new distributor rotor
5. Spark plug cables defective or
crossed5. Check for correct firing order or replace spark plug
cables. (Refer to Group 8D, Ignition System for
correct procedures.)
6. Faulty coil 6. Test and replace, if necessary (Refer to group 8D,
Ignition System)
7. Intake manifold vacuum leak 7. Inspect intake manifold gasket and vacuum hoses.
Replace if necessary
8. EGR valve leaking or stuck open 8. Test and replace, if necessary (Refer to group 25,
Emission Control Systems)
ENGINE MISSES
ON
ACCELERATION1. Worn or incorrectly gapped spark
plugs1. Replace spark plugs or clean and set gap. (Refer
to group 8D, Ignition System)
2. Spark plug cables defective or
crossed2. Replace or rewire secondary ignition cables. Refer
to Group 8D, Ignition System
3. Dirt in fuel system 3. Clean fuel system
4. Burned, warped or pitted valves 4. Install new valves
5. Faulty coil 5. Test and replace as necessary (refer to group 8D,
Ignition System)
MECHANICAL DIAGNOSIS CHARTÐGASOLINE ENGINES
CONDITION POSSIBLE CAUSES CORRECTION
NOISY VALVES/
LIFTERS1. High or low oil level
in crankcase1. Check for correct oil level. Adjust oil level by draining or adding
as needed
2. Thin or diluted oil 2. Change oil (Refer to Engine Oil Service in this group)
3. Low oil pressure 3. Check engine oil level. If ok, Perform oil pressure test. Refer to
this group for engine oil pressure test/specifications
4. Dirt in tappets/lash
adjusters4. Clean/replace hydraulic tappets/lash adjusters
5. Bent push rod(s) 5. Install new push rods
6. Worn rocker arms 6. Inspect oil supply to rocker arms and replace worn arms as
needed
7. Worn tappets/lash
adjusters7. Install new hydraulic tappets/lash adjusters
8. Worn valve guides 8. Inspect all valve guides and replace as necessary
9. Excessive runout of
valve seats or valve
faces9. Grind valves and seats
DN5.9L ENGINE 9 - 143
DIAGNOSIS AND TESTING (Continued)

Downloaded from www.Manualslib.com manuals search engine Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise, the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Clean the spark plug recesses with compressed
air.
(2) Remove the spark plugs.
(3) Secure the throttle in the wide-open position.
(4) Disconnect the ignition coil.
(5) Insert a compression pressure gauge and rotate
the engine with the engine starter motor for three
revolutions.
(6) Record the compression pressure on the third
revolution. Continue the test for the remaining cylin-
ders.
Refer to Engine Specifications for the correct
engine compression pressures.
CYLINDER HEAD GASKET FAILURE DIAGNOSIS
A cylinder head gasket leak can be located between
adjacent cylinders or between a cylinder and the
adjacent water jacket.
²Possible indications of the cylinder head gasket
leaking between adjacent cylinders are:
²Loss of engine power
²Engine misfiring
²Poor fuel economy
²Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
²Engine overheating
²Loss of coolant
²Excessive steam (white smoke) emitting from
exhaust
²Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test in this
section. An engine cylinder head gasket leaking
between adjacent cylinders will result in approxi-
mately a 50±70% reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
If a large combustion/compression pressure leak
exists, bubbles will be visible in the coolant.COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also
be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.
CYLINDER COMBUSTION PRESSURE LEAKAGE
TEST
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing)
²Leaks between adjacent cylinders or into water
jacket
²Any causes for combustion/compression pressure
loss
WARNING: DO NOT REMOVE THE RADIATOR CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE.
SERIOUS BURNS FROM HOT COOLANT CAN
OCCUR.
Check the coolant level and fill as required. DO
NOT install the radiator cap.
Start and operate the engine until it attains nor-
mal operating temperature, then turn OFF the
engine.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
Calibrate the tester according to the manufactur-
er's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379
kPa (200 psi) maximum and 552 kPa (80 psi) recom-
mended.
Perform the test procedure on each cylinder accord-
ing to the tester manufacturer's instructions. While
testing, listen for pressurized air escaping through
the throttle body, tailpipe or oil filler cap opening.
Check for bubbles in the radiator coolant.
9 - 146 5.9L ENGINEDN
DIAGNOSIS AND TESTING (Continued)

Downloaded from www.Manualslib.com manuals search engine (2) Check intake manifold bolt torque.
(3) Perform cylinder compression test. Refer to
Cylinder Compression Pressure Test in the Engine
Diagnosis area of this section.
(4) Clean or replace spark plugs as necessary and
adjust gap as specified in Electrical Group 8D.
Tighten to specifications.
(5) Test resistance of spark plug cables. Refer to
Electrical Group 8D, Spark Plug Cables.
(6) Inspect the primary wires. Test coil output volt-
age and primary resistance. Replace parts as neces-
sary. Refer to Electrical Group 8D, for specifications.
(7) Test fuel pump for pressure. Refer to Group 14,
Fuel System Specifications.
(8) The air filter elements should be replaced as
specified in Lubrication and Maintenance, Group 0.
(9) Inspect crankcase ventilation system as out
lined in Group 0, Lubrication and Maintenance. For
emission controls see Group 25, Emission Controls
for service procedures.
(10) Road test vehicle as a final test.
ENGINE OIL
WARNING: NEW OR USED ENGINE OIL CAN BE
IRRITATING TO THE SKIN. AVOID PROLONGED OR
REPEATED SKIN CONTACT WITH ENGINE OIL.
CONTAMINANTS IN USED ENGINE OIL, CAUSED BY
INTERNAL COMBUSTION, CAN BE HAZARDOUS TO
YOUR HEALTH. THOROUGHLY WASH EXPOSED
SKIN WITH SOAP AND WATER. DO NOT WASH
SKIN WITH GASOLINE, DIESEL FUEL, THINNER, OR
SOLVENTS, HEALTH PROBLEMS CAN RESULT. DO
NOT POLLUTE, DISPOSE OF USED ENGINE OIL
PROPERLY.
ENGINE OIL SPECIFICATION
CAUTION: Do not use non-detergent or straight
mineral oil when adding or changing crankcase
lubricant. Engine failure can result.
API SERVICE GRADE CERTIFIED
In gasoline engines, use an engine oil that is API
Service Grade Certified (Fig. 12). Standard engine oil
identification notations have been adopted to aid in
the proper selection of engine oil. The identifying
notations are located on the label of engine oil plastic
bottles and the top of engine oil cans. MOPAR only
provides engine oil that conforms to this certification.
SAE VISCOSITY
An SAE viscosity grade is used to specify the vis-
cosity of engine oil. SAE 10W-30 specifies a multiple
viscosity engine oil. These are specified with a dualSAE viscosity grade which indicates the cold-to-hot
temperature viscosity range. When choosing an
engine oil, consider the range of temperatures the
vehicle will be operated in before the next oil change.
Select an engine oil that is best suited to your area's
particular ambient temperature range and variation
(Fig. 13).
ENERGY CONSERVING OIL
An Energy Conserving type oil is recommended for
gasoline engines. The designation of ENERGY CON-
SERVING is located on the label of an engine oil con-
tainer.
OIL LEVEL INDICATOR (DIPSTICK)
The engine oil level indicator is located at the right
front of the engine, left of the generator on 5.9L
engines (Fig. 14).
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil,
oil foaming and oil pressure loss can result.
To ensure proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
The acceptable levels are indicated between the ADD
and SAFE marks on the engine oil dipstick.
(1) Position vehicle on level surface.
Fig. 12 Engine Oil Container Standard Notations
Fig. 13 Temperature/Engine Oil Viscosity
Recommendation
9 - 150 5.9L ENGINEDN
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine Damaged or worn threads can be repaired. Essen-
tially, this repair consists of:
²Drilling out worn or damaged threads.
²Tapping the hole with a special Heli-Coil Tap, or
equivalent.
²Installing an insert into the tapped hole to bring
the hole back to its original thread size.
CYLINDER BOREÐHONING
Before honing, stuff plenty of clean shop towels
under the bores and over the crankshaft to keep
abrasive materials from entering the crankshaft
area.
(1) Used carefully, the Cylinder Bore Sizing Hone
C-823, equipped with 220 grit stones, is the best tool
for this job. In addition to deglazing, it will reduce
taper and out-of-round, as well as removing light
scuffing, scoring and scratches. Usually, a few strokes
will clean up a bore and maintain the required lim-
its.
CAUTION: DO NOT use rigid type hones to remove
cylinder wall glaze.
(2) Deglazing of the cylinder walls may be done if
the cylinder bore is straight and round. Use a cylin-
der surfacing hone, Honing Tool C-3501, equipped
with 280 grit stones (C-3501-3810). about 20-60
strokes, depending on the bore condition, will be suf-
ficient to provide a satisfactory surface. Using honing
oil C-3501-3880, or a light honing oil, available from
major oil distributors.
CAUTION: DO NOT use engine or transmission oil,
mineral spirits, or kerosene.
(3) Honing should be done by moving the hone up
and down fast enough to get a crosshatch pattern.The hone marks should INTERSECT at 50É to 60É
for proper seating of rings (Fig. 17).
(4) A controlled hone motor speed between 200 and
300 RPM is necessary to obtain the proper cross-
hatch angle. The number of up and down strokes per
minute can be regulated to get the desired 50É to 60É
angle. Faster up and down strokes increase the cross-
hatch angle.
(5) After honing, it is necessary that the block be
cleaned to remove all traces of abrasive. Use a brush
to wash parts with a solution of hot water and deter-
gent. Dry parts thoroughly. Use a clean, white, lint-
free cloth to check that the bore is clean. Oil the
bores after cleaning to prevent rusting.
HYDROSTATIC LOCK
When an engine is suspected of hydrostatic lock
(regardless of what caused the problem), follow the
steps below.
(1) Perform the Fuel Pressure Release Procedure
(refer to Group 14, Fuel System).
(2) Disconnect the battery negative cable.
(3) Inspect air cleaner, induction system and
intake manifold to ensure system is dry and clear of
foreign material.
(4) Place a shop towel around the spark plugs to
catch any fluid that may possibly be under pressure
in the cylinder head. Remove the plugs from the
engine.
CAUTION: DO NOT use the starter motor to rotate
the crankshaft. Severe damage could occur.
(5) With all spark plugs removed, rotate the crank-
shaft using a breaker bar and socket.
Fig. 16 Oil Filter Sealing SurfaceÐTypical
1 ± SEALING SURFACE
2 ± RUBBER GASKET
3 ± OIL FILTER
Fig. 17 Cylinder Bore Crosshatch Pattern
1 ± CROSSHATCH PATTERN
2 ± INTERSECT ANGLE
9 - 152 5.9L ENGINEDN
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine REMOVALÐ4WD
(1) Disconnect the negative cable from the battery.
(2) Raise the vehicle on a hoist.
(3) Support the transmission with a transmission
jack.
(4) Remove stud nuts holding the insulator to the
crossmember (Fig. 39).
(5) Raise rear of transmission SLIGHTLY.
(6) Remove bolts holding the insulator to the insu-
lator bracket (Fig. 39). Remove the insulator.
INSTALLATIONÐ4WD
(1) If the insulator bracket was removed, install
the bracket to the transmission (Fig. 39). Tighten the
bolts to 28 N´m (250 in. lbs.) torque.
(2) Install the bolts holding insulator to insulator
bracket. Tighten the bolts to 28 N´m (250 in. lbs.)
torque.
(3) Lower rear of transmission while aligning the
insulator studs into the mounting support bracket.Install stud nuts and tighten to 28 N´m (250 in. lbs.)
torque.
(4) Remove the transmission jack.
(5) Lower the vehicle.
(6) Connect the negative cable to the battery.
ENGINE ASSEMBLY
REMOVAL
(1) Scribe hood hinge outlines on hood. Remove the
hood.
(2) Remove the battery.
(3) Drain cooling system. Refer to COOLING SYS-
TEM.
(4) Remove the air cleaner assembly and air inlet
hose.
(5) Disconnect the radiator and heater hoses.
(6) Set fan shroud aside.
(7) Remove the vacuum lines.
(8) Remove the distributor cap and wiring.
(9) Disconnect the accelerator linkage.
(10) Remove throttle body.
(11) Perform the Fuel System Pressure release
procedure Refer to FUEL SYSTEM.
(12) Disconnect the fuel lines.
(13) Disconnect the starter wires.
(14) Disconnect the oil pressure wire.
Fig. 37 Engine Mount Insulator at FrameÐ4WD
Vehicles
1 ± NUT
2 ± ENGINE SUPPORT BRACKET
3 ± INSULATOR
4 ± NUT
5 ± THROUGH BOLT
6 ± FRAME
7 ± FRONT AXLE
Fig. 38 Rear InsulatorÐ2WD Vehicles
1 ± ENGINE SUPPORT BRACKET
2 ± THROUGH BOLT
3 ± CROSSMEMBER
4 ± INSULATOR
5 ± TRANSMISSION EXTENSION
DN5.9L ENGINE 9 - 161
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine (15) Discharge the air conditioning system, if
equipped. Refer to HEATING and AIR CONDITION-
ING.
(16) Disconnect the air conditioning hoses.
(17) Disconnect the power steering hoses, if
equipped.
(18) Remove starter motor. Refer to STARTING
SYSTEMS.
(19) Remove the generator.
(20) Raise and support the vehicle on a hoist.
(21) Disconnect exhaust pipe at manifold.
(22) Remove Transmission. Refer to TRANSMIS-
SIONS.
CAUTION: DO NOT lift the engine by the intake
manifold.
(23) Install an engine lifting fixture.
(24)2WD VEHICLESÐRemove engine front
mount bolts.
(25)4WD VEHICLESÐThe engine and front
driving axle (engine/axle/transmission) are connectedthrough insulators and support brackets. Separate
the engine as follows:
²LEFT SIDEÐRemove 2 bolts attaching
(engine/pinion nose/transmission) bracket to trans-
mission bell housing. Remove 2 bracket to pinion
nose adaptor bolts. Separate engine from insulator by
removing upper nut washer assembly and bolt from
engine support bracket.
²RIGHT SIDEÐRemove 2 bracket to axle (dis-
connect housing) bolts and a bracket to bell housing
bolt. Separate engine from insulator by removing
upper nut washer assembly and bolt from engine
support bracket.
(26) Lower the vehicle.
(27) Install engine assembly on engine repair
stand.
INSTALLATION
(1) Remove engine from the repair stand and posi-
tion in the engine compartment.
(2) Install an engine support fixture.
(3) Raise and support the vehicle on a hoist.
(4) Install the engine front mounts.
(5) Refer to Group, 21 Transmissions for transmis-
sion installation
(6) Install the inspection plate.
(7) Remove transmission support.
(8) Install exhaust pipe to manifold.
(9) Lower the vehicle.
(10) Remove engine lifting fixture.
(11) Install the generator.
(12) Install starter motor.
(13) Connect power steering hoses, if equipped.
(14) Connect air conditioning hoses.
(15) Evacuate and charge the air conditioning sys-
tem, if equipped.
(16) Using a new gasket, install throttle body.
Tighten the throttle body bolts to 23 N´m (200 in.
lbs.) torque.
(17) Connect the accelerator linkage.
(18) Connect the starter wires.
(19) Connect the oil pressure wire.
(20) Install the distributor cap and wiring.
(21) Connect the vacuum lines.
(22) Connect the fuel lines.
(23) Install the radiator. Connect the radiator
hoses and heater hoses.
(24) Install fan shroud in position.
(25) Fill cooling system.
(26) Install the air cleaner assembly and air inlet
hose.
(27) Install the battery.
(28) Warm engine and adjust.
(29) Install hood and line up with the scribe
marks.
(30) Road test vehicle.
Fig. 39 Rear InsulatorÐ4WD Vehicles
1 ± AUTOMATIC TRANSMISSION
2 ± INSULATOR BRACKET
3 ± INSULATOR
4 ± CROSSMEMBER
9 - 162 5.9L ENGINEDN
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine INTAKE MANIFOLD
REMOVAL
(1) Disconnect the battery negative cable.
(2) Drain the cooling system. Refer to COOLING
SYSTEM.
(3) Remove the A/C compressor. Refer to HEAT-
ING and AIR CONDITIONING.
(4) Remove the generator. Refer to CHARGING
SYSTEM.
(5) Remove the accessory drive bracket.
(6) Remove the air cleaner assembly and air inlet
hose.
(7) Perform the fuel pressure release procedure.
Refer to FUEL SYSTEM.
(8) Disconnect the fuel supply line from the fuel
rail. Refer to FUEL SYSTEM.
(9) Disconnect the accelerator linkage and, if so
equipped, the speed control and transmission kick-
down cables.
(10) Remove the distributor cap and wires.
(11) Disconnect the coil wires.
(12) Disconnect the coolant temperature sending
unit wire.
(13) Disconnect the heater hoses and bypass hose.
(14) Remove the closed crankcase ventilation and
evaporation control systems.
(15) Remove intake manifold bolts.
(16) Lift the intake manifold and throttle body out
of the engine compartment as an assembly.
(17) Remove and discard the flange side gaskets
and the front and rear cross-over gaskets.
(18) Remove the throttle body bolts and lift the
throttle body off the intake manifold (Fig. 40). Dis-
card the throttle body gasket.
INSTALLATION
(1) If the plenum pan was removed, position pan
gasket and pan.
(2) Install plenum pan retaining bolts. (Fig. 41).
(3) Tighten plenum pan mounting bolts as follows:
²Step 1. Tighten bolts to 5.4 N´m (24 in. lbs.)
²Step 2. Tighten bolts to 9.5 N´m (84 in. lbs.)
²Step 3. Check all bolts are at 9.5 N´m (84 in.
lbs.)
(4) Using a new gasket, install the throttle body
onto the intake manifold. Tighten the bolts to 23 N´m
(200 in. lbs.) torque.
(5) Apply a bead of Mopar Silicone Rubber Adhe-
sive Sealant, or equivalent, to the four corner joints.
The sealant bead height should be slightly higher
than the cross-over gaskets, approximately 5 mm (0.2
in). An excessive amount of sealant is not required to
ensure a leak proof seal, and an excessive amount of
sealant may reduce the effectiveness of the flange
gasket.
(6) Install the front and rear cross-over gaskets
onto the engine (Fig. 42).
(7) Install the flange gaskets. Ensure that the ver-
tical port alignment tab is resting on the deck face of
the block. Also the horizontal alignment tabs must be
in position with the mating cylinder head gasket tabs
(Fig. 43). The words MANIFOLD SIDE should be vis-
ible on the center of each flange gasket.
(8) Carefully lower intake manifold into position
on the cylinder block and cylinder heads. long studs
at the front and rear of the manifold will help to
align the intake manifold. After intake manifold is in
Fig. 40 Throttle Body Assembly
1 ± FUEL RAIL ASSEMBLY
2 ± FUEL RAIL MOUNTING BOLTS
3 ± FUEL RAIL CONNECTING HOSES
Fig. 41 Plenum Pan Bolt Tightening Sequence
DN5.9L ENGINE 9 - 163
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine place, inspect to make sure seals are in place.
Remove alignment studs if used.
(9) The following torque sequence duplicates the
expected results of the automated assembly system
(Fig. 44).
²Step 1ÐTighten bolts 1 thru 4, in sequence, to 8
N´m (72 in. lbs.) torque. Tighten in alternating steps
1.4 N´m (12 in. lbs.) torque at a time.
²Step 2ÐTighten bolts 5 thru 12, in sequence, to
8 N´m (72 in. lbs.) torque.
²Step 3ÐCheck that all bolts are tightened to 8
N´m (72 in. lbs.) torque.
²Step 4ÐTighten all bolts, in sequence, to 16 N´m
(12 ft. lbs.) torque.
²Step 5ÐCheck that all bolts are tightened to 16
N´m (12 ft. lbs.) torque.
(10) Install closed crankcase ventilation and evap-
oration control systems.
(11) Install the coil wires.
(12) Connect the coolant temperature sending unit
wire.
(13) Connect the heater hoses and bypass hose.
(14) Install distributor cap and wires.
(15) Connect the accelerator linkage and, if so
equipped, the speed control and transmission kick-
down cables.
(16) Install the fuel supply line to the fuel rail.
(17) Install the accessory drive bracket and A/C
compressor.(18) Install the generator and accessory drive belt.
Tighten generator mounting bolt to 41 N´m (30 ft.
lbs.) torque.
(19) Install the air cleaner assembly and air inlet
hose.
(20) Fill cooling system.
(21) Connect the battery negative cable.
Fig. 42 Cross-Over Gaskets
1 ± FRONT CROSS-OVER GASKET
2 ± REAR CROSS-OVER GASKET
Fig. 43 Intake Manifold Flange Gasket Alignment
1 ± FLANGE GASKET
2 ± ALIGNMENT TABS
3 ± CYLINDER HEAD GASKET
Fig. 44 Intake Manifold Bolt Tightening SequenceÐ
5.9L Engine
9 - 164 5.9L ENGINEDN
REMOVAL AND INSTALLATION (Continued)