fuel tank removal DODGE TRUCK 1993 Service Repair Manual

LUBRICATION
AND
MAINTENANCE
0-11

J
DRIVE-ON
HOIST

I
FRAME
CONTACT
HOIST
TWIN
POST
CHASSIS
HOIST

FLOOR
JACK
RROOD30
Fig.
8 Correct Vehicle Lifting
Locations
An axle tube
A body side sill
A steering linkage component
A drive shaft
The engine or transmission oil pan
The fuel tank
• A front suspension arm Use the correct frame rail lifting locations only
(Fig. 8).
HOIST A vehicle can be lifted with:
• A single-post, frame-contact hoist
• A twin-post, chassis hoist
• A ramp-type, drive-on hoist
When a frame-contact type hoist is used, verify
that the lifting pads are positioned properly (Fig. 8).

WARNING:
WHEN
A
SERVICE
PROCEDURE
RE­
QUIRES
THE
REMOVAL
OF
THE
REAR
AXLE,
FUEL

TANK,
OR
SPARE
TIRE,
EITHER:

• PLACE ADDITIONAL WEIGHT ON THE REAR
END OF THE VEHICLE
« ATTACH THE VEHICLE TO THE HOIST
« PLACE JACK STANDS UNDER THE VEHICLE
FOR SUPPORT TO PREVENT TIPPING WHEN
THE CENTER OF BALANCE CHANGES
4WD VEHICLES A standard hoist can be used to lift a 4WD vehicle.
The hoist should be inspected for adequate clearance. The lift arms, pads or ramps should be adjusted to
ensure that there is adequate clearance (Fig. 9).
ADJUSTMENT
PAD

ii 7
MAINTAIN
CLEARANCE
HOIST
ARM

RK44

Fig.
9 Lifting 4WD Vehicle
With
Single-Post
Hoist—
Typical
When a twin-post hoist is used, a 4 x 4 x 12-inch
wood spacer also could be required. Place the wood spacer under the front axle (opposite the differential
housing). This will maintain balance and level lift­ ing.

CAUTION:
The
block
that
is
used must
be
secured in
a
safe manner. This
will
ensure
that
it
will
not un­

balance
the
vehicle.
VEHICLE
TOWING
RECOMMENDATIONS
When it is necessary to tow a Ram Truck, the rec­
ommended method is either:
• the sling-type, rear-end raised towing method; or
• the wheel-lift towing method with a tow dolly lo­
cated under the front wheels. A vehicle with flat-bed hauling equipment can also
be used to transport a disabled vehicle.

SLING-TYPE
FLAT
BED
RR0OD29
Fig.
10 Tow Vehicles
With
Approved
Equipment

5.2L
ENGINE
9 - 47

S.2L ENGINE
SERVICE
PROCEDURES

INDEX

page

Camshaft
. , . 61

Crankshaft
68

Crankshaft Main Bearings
69

Crankshaft Rear
Oil
Seals
...... ........
70

Cylinder Block ...........................
71

Cylinder Head Cover
. . . . 51

Cylinder Heads
52
Distributor
62

Engine
Assembly
. 50

Engine
Front Mounts
47

Engine
Rear Mount ...............
48

Front Crankshaft
Oil
Seal Replacement
. . 61

GENERAL
INFORMATION
The 5.2 Liter (318 CID) eight-cylinder engine is a
V-Type lightweight, single cam, overhead valve en­ gine with hydraulic roller tappets (Fig. J).

Engine
Type ....
90° V-8 OHV

Bore
and Stroke .....
99.3
x
84.0 mm
(3.91
x
3.31
in.)

Displacement................
5.2L(318cu.
in.)

Compression
Ratio ....... .
9.1:1

Torque .. 379 N-m (280
ft.
lbs.)
@
3,200
rpm

Firing Order .... 1-8-4-3-6-5-7-2

Lubrication
.......
Pressure
Feed-Full Flow
Filtration

Engine
Oil
Capacity......
4.7L
(5.0 Qts)
with Filter

Cooling System ...... Liquid Cooled-Forced
Circulation

Cooling Capacity..........
16.1L(17.0Qts)

Ramcharger
15.6L
(16.5 Qts)
Cylinder Block
,
Cast
Iron
Crankshaft Nodular Iron
Cylinder Head ..............
Cast
Iron
Combustion Chambers
..
Wedge-High
Swirl Valve Shrouding
Camshaft Nodular Cast Iron

Pistons
Aluminum Alloy
w/Strut

Connecting
Rods...........
Forged
Steel

J9309-41

Fig. 1
Engine
Description
This engine is designed for unleaded fuel.
Engine lubrication system consists of a rotor type
oil pump and a full flow oil filter.
The cylinders are numbered from front to rear; 1?

3,
5, 7 on the left bank and 2, 4, 6, 8 on the right
bank. The firing order is 1-8-4-3-6-5-7-2 (Fig. 2).
The engine serial number is stamped into a ma­
chined pad located on the left, front corner of the cyl­
inder block. When component part replacement is
necessary, use the engine type and serial number for
reference (Fig. 3).
page

General
Information
.......................
47
Hydraulic Tappets
57

Oil
Pan . 63

Oil Pump
. 64

Piston
/
Connecting
Rod
Assembly
66

Rocker
Arms
51

Specifications—5.2L Engine
73

Timing Chain Cover ................
59
Valve Stem Shield
/
Spring Replacement
56

Valve Timing
. 58

Valves
/
Valve Springs
54

Vibration
Damper
. . 58
J908D-49
Fig.
2 Firing Order
X
M 5.2L T
XXXX
XXXXXXXX

X
~
Last Digit of
Model
Year
M
=
Plant
- M
Mound
Road
S
Saltillo

T
Trenton

K
Toluca

5.2L
=
Engine Displacement
T
=
Usage
-
T Truck

XXXX
=
Month/Day

XXXXXXXX
=
Serial Code
-
Last
8
Digits
of
VIN
No.

J9209-73

Fig.
3
Engine
Identification
Number

ENGINE
FRONT
MOUNTS

REMOVAL
(1) Raise hood and position fan to assure clearance
for radiator top tank and hose.

5.9L
ENGINE SERVICE PROCEDURES

INDEX

page
Camshaft
91

Crankshaft
98
Crankshaft Main Bearings
99

Crankshaft Rear
Oil
Seals
100

Cylinder
Block
101

Cylinder
Head Cover
81

Cylinder
Heads
82
Distributor
92

Engine Assembly
80

Engine
Front
Mounts
77

Engine Rear Mount
78

Front
Crankshaft
Oil
Seal Replacement
91
page
General
Information
77
Hydraulic
Tappets
87

Oil
Pan 93

Oil Pump
. 94

Piston
/
Connecting
Rod
Assembly
96

Rocker Arms
81

Specifications—5.9L
Engine
103

Timing
Chain Cover
89

Valve Stem Shield
/
Spring Replacement
86

Valve
Timing
. 88

Valves
/
Valve Springs
84

Vibration
Damper
88

GENERAL
INFORMATION
The 5.9 Liter (360 CID) eight-cylinder engine is a
V-Type lightweight, single cam, overhead valve en­
gine with hydraulic roller tappets (Fig. 1).
Engine Type .90° V-8 OHV
Bore and Stroke 101.6 x 90.9
mm
(4.00 x 3.58 in.)
Displacement 5.9L (360 cu. in.)
Compression Ratio 9.1:1
Torque 441 N-m (325 ft. lbs.) @ 3,200 rpm (Heavy Duty). 448 N-m (330 ft. lbs.)
@
2,800 rpm
Firing Order
1-8-4-3-6-5-7-2

Lubrication ...... Pressure Feed - Full Flow Filtration
Engine Oil Capacity .4.7L (5.0 Qts) w/filter
Cooling System . .
.
Liquid Cooled - Forced Circulation Cooling Capacity ..... . . 14.7L (15.5 Qts)
Ramcharger (4WD) 14.2L (15.0 Qts)
Cylinder Block Cast Iron Crankshaft
-
Nodular Iron
Cylinder Head • . Cast Iron Combustion Chambers Wedge-High Swirl Valve
Shrouding
Camshaft Nodular Cast Iron Pistons Cast Aluminum Alloy
Connecting Rods Forged Steel
J9309-99
Fig. 1
Engine
Description
This engine is designed for unleaded fuel.
Engine lubrication system consists of a rotor type
oil pump and a full flow oil filter.
The cylinders are numbered from front to rear; 1,

3,
5, 7 on the left bank and 2, 4, 6, 8 on the right
bank. The firing order is
1-8-4-3-6-5-7-2
(Fig. 2).
The engine serial number is stamped into a ma­
chined pad located on the left, front corner of the cyl­
inder block. When component part replacement is
necessary, use the engine type and serial number for
reference (Fig. 3).
o
FRONT OF
ENGINE CLOCKWISE ROTATION

1-8-4-3-6-5-7-2
J908D-49

Fig. 2 Firing Order

X
M 5.9L T
XXXX
XXXXXXXX

X
= Last Digit of Model Year
M = Plant - M Mound Road S Saltillo
T Trenton K Toluca
5.9L = Engine Displacement

T
= Usage -
T
Truck
XXXX
= Month/Day

XXXXXXXX
= Serial Code - Last 8 Digits of
VIN
No.
J9209-74

Fig.
3
Engine
identification
Number

ENGINE
FRONT MOUNTS
REMOVAL (1) Raise hood and position fan to assure clearance
for radiator top tank and hose.

•

5.9L
(DIESEL)
ENGINE
9 -
107
5.9L
(DIESEL)
ENGINE
SERVICE
PROCEDURES

INDEX

page

Camshaft
127

Crankshaft
138

Cylinder
Block
129

Cylinder
Head
113

Engine
Assembly
. 109

Engine
Front
Mounts
(Insulators
/
Brackets)
... 107

Engine
Rear Support
108

Gear
Housing
/
Cover
122

General
Information
107

Oil Cooler Element
/
Gasket
. 149
Oil
Filter
148
page

Oil
Filter
Bypass
Valve
. 148

Oil Pan
/
Suction Tube
146

Oil Pressure Regulator Valve
/
Spring
148

Oil Pump
146
Piston
/
Connecting
Rod
Assembly
134

Rocker
Levers
/
Push
Rods
112

Specifications—5.9L Diesel Engines
151

Tappet
125

Timing
Pin
123

Valve Clearance
Adjustment
...............
121

Valves
and
Valve Springs
116

GENERAL INFORMATION The
5.9
Liter
(359 CID)
six-cylinder diesel engine
is
an
In-line valve-in head type
(Fig. 1).

Fig.
1
Diesel
Engine
Description
This engine
is
designed
for No.2
Diesel Fuel. Only
use
No.l
Diesel Fuel where extended arctic condi­
tions exist (below -23°C
or -10°F).

Engine lubrication system consists
of a
gerotor
type
oil
pump
and a
full flow
oil
filter with
a
bypass valve.
The cylinders
are
numbered from front
to
rear;
1,

2,
3, 4, 5 and 6. The
firing order
is
1-5-3-6-2-4
(Fig.

2).
J898D-10
Fig.
2
Firing Order
The engine data plate
is
located
on the
driver side
of
the
engine forward
of the
fuel injection pump.
ENGINE FRONT MOUNTS (INSULATORS
/

BRACKETS)
REMOVAL (1) Raise hood
and
position
fan to
assure clearance
for radiator
top
tank
and
hose.
(2) Raise vehicle
on a
hoist. Support
the
engine.
(3) Remove
the
through-bolts
and
nuts from
the

bracket
(Fig. 3).

(4) Remove
the
nuts from insulator studs
(Fig. 3).
(5) Raise engine with
a
lifting fixture only
far

enough
to
remove
the
insulators
and
brackets. Mark
the locating
pin
position.
(6) Remove
the
engine mounting brackets from
the

engine block.
Engine Type
In-line
6
(Diesel-Turbo)
Bore and Stroke 102.0 x 120.0 mm
(4.02x4.72 in.)
Displacement 5.9L (359 cu.
in.)

Compression Ratio 17.5:1
Torque 542 N-m (400 ft. lbs.)

@
1,750 rpm
Firing Order
1-5-3-6-2-4

Lubrication Pressure Feed - Full Flow
Filtration w/Bypass Filter
Engine Oil Capacity
11.4L
(12.0 Qts) w/Filter
Cooling System Liquid Cooled
-
Forced
Circulation
Cooling Capacity
Manual Trans 15.2L (16.0 Qts)
Automatic Trans 16.2L (17.0 Qts)
Recovery Bottle 0.95L(1.0Qts)
Cylinder Block.... Cast Iron
Crankshaft Induction Hardened
Forged Steel
Cylinder Head Cast Iron
Combustion Chambers High Swirl Bowl
Camshaft.... Chilled Cast Iron
Pistons Cast Aluminum
Connecting Rods Forged Steel
J9209-48

9
- 114 5.9L
(DIESEL) ENGINE
—

Fig.
4
Exhaust
Manifold
(6) Remove the fuel lines and injector nozzles (re­
fer to Group 14, Fuel System).
(7) Remove the valve covers (Fig. 5).

Fig.
5
Valve
Cover

(8) Remove the rocker levers and push rods.
(9) Remove the fuel/water separator filter (Fig. 6).
Refer to Group 14, Fuel System, for the proper pro­
cedures.
(10) If the engine is hot, remove the cylinder head
bolts in the sequence shown in Fig. 7..The removal sequence is not important if the engine is cold. There
are 3 sizes of head bolts. Note the position of each
bolt for future installation.
(11) Remove the cylinder head and gasket from the
cylinder block.
•

Fig. 6 Fuel/Water Separator Filter J9109-36
Fig. 7 Cylinder Head Bolt Removal Sequence—Cylinder Head Hot

INSPECTION
Remove the cup plugs and inspect the coolant pas­

sages.
A large build up of rust and lime will require
removal of the cylinder block for cleaning in a hot
tank.
Inspect the cylinder bores for damage or excessive
wear. Rotate the crankshaft so the piston is at Bot­
tom Dead Center (BDC) to inspect the bores. Measure the cylinder bores (Fig. 8). DO NOT pro­
ceed with in-chassis repair if the bores are damaged
or worn beyond the limits (refer to Cylinder Bore Re­
pair - Cylinder Block).
Check the top surface for damage caused by the
cylinder head gasket leaking between cylinders.
Inspect the block and head surface for nicks, ero­
sion, etc. Check the head distortion (Fig. 9). The distortion of
the combustion deck face is not to exceed 0.010 mm (0.0004 inch) in any 50.8 mm (2.00 inch) diameter.
Overall variation end to end or side to side 0.30 mm (0.012 inch).
(3) Disconnect the radiator and heater hoses (refer
to Group 7, Cooling System). (4) Remove the turbocharger.
(5) Remove the exhaust manifold (Fig. 4).

13
- 30 FRAME AND BUMPERS
ATTACHED COMPONENTS

SKID
PLATES
TRANSFER CASE SKID
PL
ATF
4 WD
VEHICLES

REMOVAL
(1) Position
a
support under
the
skid plate.
(2) Remove
the
bolts that attach
the
skid plate
to

the frame crossmember. Remove
the
bolts
for the

crossmember support
to the
frame rail.
(3) Remove
the
crossmember support
and the
skid
plate.

INSTALLATION
(1) Position
and
support
the
skid plate
and the

crossmember support
at the
frame rail. Align
the

bolt holes.
(2) Insert
the
bolts through
the
frame crossmember
and frame rail. Install
the
nuts. Tighten
to 23 N*m

(200
in. lbs.)
torque.
(3) Remove
the
support from under
the
skid plate.
Fig.
1
Transfer
Case Skid
Plate—4WD Vehicles
FUEL TANK SKID
PLATE-4WD
VEHICLES
REMOVAL

(1) Position
a
support under
the
fuel tank skid
plate.
(2) Remove
the
nuts
and
bolts that attach
the
skid
plate
to the
frame rails, rear crossmember
and the
support bracket.
(3) Remove
the
skid plate from
the
fuel tank
and

the vehicle.

INSTALLATION
(1) Position
and
support
the
skid plate under
the

fuel tank. Insert
the
studs
in the
support bracket.
(2) Install
the
nuts
to
attach
the
skid plate
to the

support bracket. Install
the
bolts
at the
rear cross- member. Install
the
bolts
at the
frame side rails.
Tighten
the
nuts
and
bolts
to 23 N*m (200 in. lbs.)

torque.
(3) Remove
the
support from under
the
skid plate.
FRAME FRAME

Fig.
2
Fuel
Tank
Skid
Plate-4WD Vehicles

SPARE
TIRE/WHEEL
CARRIER
REMOVAL
(1) Remove
the nut and
insert from
the
support
rod. (2) Lower
the
hanger
and
remove
the
spare tire/
wheel from
the
underside
of the
frame crossmember.
(3) Remove
the
retaining
nut,
lockwasher
and

hanger from
the
left frame rail.
(4) Refer
to
removal procedures
for
installation. BOLT BOLT FRAME

Fig.
3
Spare
The/Wheel Carrier

•

FUEL
SYSTEM
14 - 1

FUEL
SYSTEM

page

ACCELERATOR
PEDAL
AND THROTTLE
CABLE
................ 25

DIESEL
FUEL
INJECTION-COMPONENT
DESCRIPTION/SYSTEM
OPERATION
76

DIESEL
FUEL
INJECTION-GENERAL

DIAGNOSIS
88

DIESEL
FUEL
INJECTION-SERVICE

PROCEDURES
....................... 106

FUEL
DELIVERY
SYSTEM-EXCEPT
DIESEL
.. 3

FUEL
DELIVERY-DIESEL
ENGINE
15

FUEL
TANKS
.... 20
page

GENERAL
INFORMATION 1

MULTI-PORT
FUEL
INJECTION (MPI)-
COMPONENT
DESCRIPTION/SYSTEM

OPERATION-EXCEPT
DIESEL
29

MULTI-PORT
FUEL
INJECTION (MPI)-
COMPONENT
REMOVAL/INSTALLATION-

EXCEPT
DIESEL
64

MULTI-PORT
FUEL
INJECTION (MPI)-
GENERAL
DIAGNOSIS-EXCEPT
DIESEL
...43

SERVICE
ADJUSTMENTS-DIESEL
122

SPECIFICATIONS
123

GENERAL INFORMATION

Throughout this group, references are made to par­
ticular vehicle models by alphabetical designation or
by the particular vehicle nameplate. A chart showing a breakdown of the alphabetical designations is in­
cluded in the Introduction section at the beginning of
this manual.
The 5.9L (V-8) gas powered engine will be referred
to in this group as either the: LDC (Light Duty Cy­ cle) or HDC (Heavy Duty Cycle) engine. The HDC engine can be easily identified by the use of an en­
gine mounted air injection pump. The 3.9L/5.2L/5.9L
LDC engine will not use an air injection pump.
This Fuel System group will cover all fuel system
components for the 3.9L (V-6), 5.2L (V-8), 5.9L LDC
(V-8),
5.9L HDC (V-8) and 5.9L (in-line six cylinder)
diesel engines.
The Fuel System consists of: the fuel tank, an
electric (fuel tank mounted) fuel pump and fuel fil­
ter. It also consists of fuel tubes/lines/hoses, vacuum

hoses,
throttle body and fuel injector(s).
The Fuel Delivery System consists of: the electric
fuel pump, fuel filter, fuel tubes/lines/hoses, fuel rail,
fuel injectors and fuel pressure regulator.
A Fuel Return System is used on all vehicles (all
engines) except the 5.9L (V-8) gas powered engine. On this engine, a returnless type fuel system is
used. The fuel return system consists of fuel tubes/
lines and hoses that route fuel back to the fuel tank.
The Fuel Tank Assembly consists of: the fuel
tank, filler tube, fuel gauge sending unit/electric fuel
pump module, a pressure relief/rollover valve and a
pressure-vacuum filler cap. Also to be considered part of the fuel system is the
Evaporation Control System. This is designed to
reduce the emission of fuel vapors into the atmo­ sphere. The description and function of the Evapora­
tive Control System is found in Group 25, Emission Control Systems.

FUEL
USAGE
STATEMENT-GAS
ENGINES
Your vehicle was designed to meet all emission
regulations and provide excellent fuel economy using
high quality unleaded gasoline. Only use unleaded gasolines having a minimum posted octane of 87. If your vehicle develops occasional light spark
knock (ping) at low engine speeds, this is not harm­

ful.
However, continued heavy knock at high speeds can cause damage and should be re­
ported to your dealer immediately. Engine dam­ age as a result of heavy knock operation may not be
covered by the new vehicle warranty. In addition to using unleaded gasoline with the
proper octane rating, those that contain deter­

gents,
corrosion and stability additives are rec­
ommended. Using gasolines that have these additives will help improve fuel economy, reduce
emissions and maintain vehicle performance. Gener­ ally, premium unleaded gasolines contain more addi­
tive than regular unleaded gasolines. Poor quality gasoline can cause problems such as
hard starting, stalling and stumble. If you experience
these problems, use another brand of gasoline before considering service for the vehicle.

14-4
FUEL
SYSTEM

•

Fig.
3 Top View of
Fuel
Pump
Module—5.9L
Engine
FUEL
PUMP

The fuel pump used in this system has a perma­
nent magnet electric motor. The pump is part of the
fuel pump module (Fig. 2). The fuel pump module is suspended in fuel in the fuel tank. Fuel is drawn in
through a filter and pushed through the electric mo­
tor to the outlet. The pump contains a check valve.
This valve is located near the pump outlet. It re­ stricts fuel movement in either direction to maintain
fuel supply line pressure when the pump is not oper­ ational. Voltage to operate the pump is supplied
through the auto shut down (ASD) and fuel pump re­
lays.

WARNING:
THE
FUEL SYSTEM
IS
UNDER
A
CON­ STANT PRESSURE (EVEN
WITH
THE
ENGINE OFF).
BEFORE
SERVICING
THE
FUEL PUMP, FUEL

TUBES
(LINES), FUEL FILTER,
OR
FUEL
INJEC­

TOR^),
THE
FUEL SYSTEM PRESSURE MUST
BE
RELEASED.

FUEL
PUMP
REPLACEMENT

The fuel pump is not serviceable. If the fuel pump
needs replacement, the complete fuel pump module must be replaced. Perform the Fuel System Pressure
Release procedure before servicing the fuel pump.

FUEL
PUMP
MODULE
REMOVAL

WARNING:
THE
FUEL SYSTEM
IS
UNDER
A
CON­ STANT PRESSURE (EVEN
WITH
THE
ENGINE OFF).
BEFORE
SERVICING
THE
FUEL PUMP MODULE,
THE FUEL SYSTEM PRESSURE MUST
BE RE­
LEASED.

CAUTION:
Whenever
the
fuel
pump
module
is
ser­
viced,
the
locknut
and gasket
must
be replaced. (1) Drain the fuel tank. Refer to Draining Fuel
Tank in the Fuel Tank section of this group.
(2) Remove fuel tank. Refer to the Fuel Tank sec­
tion of this group.
(3) The fuel pump module locknut is threaded onto
the fuel tank. Remove the fuel pump module locknut
(Figs.
1 or 3). The fuel pump module will spring up
when the locknut is removed.

(4)
Remove module from fuel tank.

DISASSEMBLY-
FUEL GAUGE SENDING
UNIT
(1) Remove sending unit mounting screws (Fig. 4).
(2) Mark the sending unit electrical wires before

FUEL
GAUGE
TABS

IN-TANK

FUEL
FILTER
J9114-146

Fig.
4
Module
Service—Typical
removal for correct installation. Carefully disconnect electrical wires from sending unit. Remove sending unit.
(3) Reverse order of removal for installation.

IN-TANK FUEL FILTER
The in-tank filter is attached to the bottom of the
fuel pump module (Fig. 4).
(1) Pry the mounting tabs back and remove the in-
tank fuel filter.
(2) Install new fuel filter into retaining tabs.

FUEL
PUMP
MODULE
INSTALLATION

CAUTION:
Whenever
the
fuel
pump
module
is
ser­
viced,
the
locknut
and
gasket must
be
replaced.

(1) Using a new gasket, position fuel pump module
into opening in fuel tank. (2) Position new locknut over top of fuel pump
module. (3) Tighten locknut. (4) Install fuel tank. Refer to Fuel Tank Installa­
tion in this section.

•

FUEL SYSTEM
14-5
FUEL PUMP CONTROL

The powertrain control module (PCM) computer en­
ergizes the fuel pump through the automatic shut
down (ASD) and fuel pump relays. Battery voltage is applied to the relay from the ignition switch. The coil
in the relay is energized when a ground is provided
by the PCM. The relays are located in the engine compartment (Fig. 5).

DATA
UNK
CONTROL

CONNECTOR
MODULE
J9314-164

Fig.
5
Fuel
Pump
and ASD
Relays

FUEL
SYSTEM
PRESSURE
RELEASE

ALL
GAS
ENGINES
The fuel system is under constant fuel pressure
(even with the engine off).
WARNING: BECAUSE THE FUEL SYSTEM IS UN­ DER CONSTANT FUEL PRESSURE, THIS PRES­
SURE MUST BE RELEASED BEFORE SERVICING
ANY FUEL SUPPLY OR FUEL RETURN SYSTEM COMPONENT. THIS DOES NOT APPLY TO THROT­
TLE BODY REMOVAL.
(1) Disconnect negative battery cable.
(2) Remove the fuel tank filler tube cap to release
fuel tank pressure. (3) Remove protective cap from pressure test port
on the fuel rail (Figs. 6, 7 or 8).
WARNING: DO NOT ALLOW FUEL TO SPILL ONTO
THE ENGINE INTAKE OR EXHAUST MANIFOLDS. PLACE SHOP TOWELS UNDER AND AROUND THE
PRESSURE PORT TO ABSORB FUEL WHEN THE
PRESSURE IS RELEASED FROM THE FUEL RAIL.
WARNING: WEAR PROPER EYE PROTECTION
WHEN RELEASING FUEL SYSTEM PRESSURE.
(4) Obtain the fuel pressure gauge/hose assembly
from fuel pressure gauge tool set 5069. Remove the
gauge from the hose.
CONNECTOR
HOSES
J9214-27

Fig.
7
Fuel
Pressure
Test Port—5.2L (V-8)
Engine
(5) Place one end of hose (gauge end) into an ap­
proved gasoline container. (6) Place a shop towel under the test port.
(7) To release fuel pressure, screw the other end of
hose onto the fuel pressure test port.
(8) After fuel pressure has been released, remove
the hose from the test port. (9) Install protective cap to fuel test port.

FUEL SYSTEM
PRESSURE
TEST-3.9L/5.2L

ENGINE
Fuel systems on vehicles equipped with a 3.9L or

•

FUEL
SYSTEM
14 - 9 (2) Start the vehicle and let engine idle. Check
fuel pressure reading on gauge. Fuel pressure should
be within specifications. Refer to the previous Fuel System Pressure Tests.
(3) Shut engine off. Observe and record fuel pres­
sure reading on gauge. Leave fuel pressure gauge
connected. Allow engine to set for 30 minutes and
then compare the fuel pressure reading on the gauge
with the reading taken when engine was shut down.
A pressure drop of up to 138 kPa (20 psi) within 30 minutes is within specifications.
(4) If the fuel pressure drop is within specifica­

tions,
the fuel pump outlet check valve and fuel pres­ sure regulator are both operating normally.

(5)
If fuel pressure drop is greater than 138 kPa
(20 psi), it must be determined if this drop is being
caused by (in-tank mounted) fuel pump outlet check
valve or fuel pressure regulator. Proceed to next step. (6) Release the fuel system pressure from fuel sys­
tem. Refer to the previous Fuel Pressure Release
Procedure in this group. (7) Disconnect both fuel tubes (lines) at fuel rail
near fuel pressure regulator. (8) Connect Fuel Line (Tube) Pressure Test
Adapter Tool number 6631 (3/8 in.) between the dis­ connected fuel supply line and fuel rail (Fig. 17). (9) Connect Fuel Line (Tube) Pressure Test
Adapter Tool number 6539 (5/16 in.) between the dis­
connected fuel return line and fuel rail (Fig. 17).
Fig. 17 Adapter Tools—Typical Connections
(10) Start engine. Observe and record fuel system
pressure.
(11) Shut engine off.
(12) Clamp off the rubber hose portion of adapter
tool number 6539 connected to the fuel return line.
Allow engine to set for 30 minutes. If pressure has
dropped more than 138 kPa (20 psi) in 30 minutes,
pressure is bleeding past the (in-tank mounted) fuel pump outlet check valve. Replace Fuel Pump Module assembly. Refer to Fuel Pump Module removal and installation in this group. If pressure drop is within
specifications, proceed to next step.
(13) Clamp off the rubber hose portion of adapter
tool number 6631 connected to the fuel supply line.
Allow engine to set for 30 minutes. If pressure has
dropped more than 138 kPa (20 psi) in 30 minutes,
pressure is bleeding past the fuel pressure regulator.
Replace fuel pressure regulator. Refer to Fuel Pres­ sure Regulator removal and installation in the Com­
ponent Removal/Installation section of this group.

FUEL
PRESSURE
LEAK DOWN TEST—5.9L

ENGINE

ENGINE OFF Abnormally long periods of cranking to restart a
hot engine that has been shut down for a short pe­
riod of time may be caused by:
• Fuel pressure bleeding past a fuel injector.
• Fuel pressure bleeding past the check valve in the
fuel filter/fuel pressure regulator.
(1) Disconnect the fuel inlet tube at fuel rail (Fig.

18).
This is done by pushing on plastic part of quick-
connect fitting on tube (Fig. 19).
Fig. 18 Fuel Pressure Test Port—5.9L Engines
(2) Connect Fuel Line (Tube) Pressure Test
Adapter Tool number 6539 (5/16 in.) between the dis­
connected fuel tube and fuel rail.
(3) Connect the 0-414 kPa (0-60 psi) fuel pressure
test gauge (from Gauge Set 5069) to the test port on
tool 6631. The fittings on both tools must be in good condition and free from any small leaks
before performing the proceeding test,
(4) Start engine and bring to normal operating
temperature.
(5) Observe test gauge. Normal operating pressure
should be 241-310 kPa (35-45 psi). (6) Shut engine off.
(7) Pressure should not fall below 24 psi for five
minutes.