fuel pump JEEP WRANGLER 1994 Owner's Manual

(29) Verify that fuel pump module wire connector
is firmly connected to harness connector.
(30) Inspect fuel hoses at fuel pump module for
cracks or leaks (Fig. 28).
(31) Inspect transmission torque convertor housing
(automatic transmission) or clutch housing (manual
transmission) for damage to timing ring on drive
plate/flywheel.
(32) Verify that battery cable and solenoid feed
wire connections to the starter solenoid are tight and
clean. Inspect for chaffed wires or wires rubbing up
against other components (Fig. 29).
POWERTRAIN CONTROL MODULE (PCM) 60-WAY
CONNECTOR
For PCM 60-way connector wiring schematics, re-
fer to Group 8W, Wiring Diagrams.
SYSTEM SCHEMATICS
Fuel system schematics for the 2.5L 4 cylinder and
4.0L 6 cylinder engines are shown in figures 30, 31,
32 and 33.
Fig. 28 Fuel Pump Module Connector and Fuel HosesÐTypical
Fig. 29 Starter Solenoid ConnectionsÐTypical
14 - 38 FUEL SYSTEMJ

harness connector terminal-2 and the sensor connec-
tor terminal. Also test terminal-4 to the sensor con-
nector terminal. Repair the wire harness as
necessary if the resistance is greater than 1 ohm.
FUEL PUMP RELAY TESTING
For testing this relay, refer to RelaysÐOperation/
Testing in this section of the group.
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR
TEST
To perform a complete test of the MAP sensor and
its circuitry, refer to DRB scan tool and appropriate
Powertrain Diagnostics Procedures manual. To test
the sensor only, refer to the following:
Inspect the MAP sensor vacuum hose connections
at the throttle body and sensor. Repair as necessary.
CAUTION: When testing, do not remove the electri-
cal connector from MAP sensor (Fig. 37). Be sure
that the MAP sensor harness wires are not dam-
aged by the test meter probes.Test the MAP sensor output voltage at the MAP
sensor connector between terminals A and B (as
marked on the sensor body) (Fig. 38). With the igni-
tion switch ON and the engine OFF, output voltage
should be 4-to-5 volts. The voltage should drop to 1.5-
to-2.1 volts with a neutral-hot idle speed condition.
Test Powertrain Control Module (PCM) (termi-
nal-5) for the same voltage described above to verify
the wire harness condition. Repair as necessary.
Test MAP sensor supply voltage at sensor connec-
tor between terminals A and C (Fig. 38) with the ig-
nition ON and engine OFF. The voltage should be
approximately 5 volts (60.5V). Five volts (60.5V)
should also be at terminal-6 of the PCM wire harness
connector. Repair or replace the wire harness as nec-
essary.
Test the MAP sensor ground circuit at sensor con-
nector terminal-A (Fig. 38) and PCM connector ter-
minal-4. Repair the wire harness if necessary.
Test the MAP sensor ground circuit at the PCM
connector between terminal-4 and terminal-11 with
an ohmmeter. If the ohmmeter indicates an open cir-
cuit, inspect for a defective sensor ground connection.
Refer to Group 8W, Wiring for location of engine
grounds. If the ground connection is good, replace the
PCM. If terminal-4 has a short circuit to 12 volts,
correct this condition before replacing the PCM.
CRANKSHAFT POSITION SENSOR TEST
Refer to Group 8D, Ignition Systems for test proce-
dures.
Fig. 36 Air Temperature SensorÐ4.0L Engine
Fig. 37 MAP SensorÐTypical
Fig. 38 MAP Sensor Connector TerminalsÐTypical
14 - 44 FUEL SYSTEMJ

found, refer to the DRB scan tool and the appropri-
ate Powertrain Diagnostics Procedures service
manual.
RELAYSÐOPERATION/TESTING
OPERATION
The following operations/tests apply to these
relays only:automatic shut down (ASD), fuel pump
and torque converter clutch. For operations/tests on
all other relays, refer to the appropriate section of
this service manual.
The relay terminal numbers from (Fig. 44) can be
found on the bottom of the relay:
²Terminal number 30 is connected to battery volt-
age and can be switched or B+ (hot) at all times.
²Terminal number 87A is connected (a circuit is
formed) to terminal 30 in the de-energized (normally
OFF) position.
²Terminal number 87 is connected (a circuit is
formed) to terminal 30 in the energized (ON) posi-
tion. Terminal number 87 then supplies battery volt-
age to the component being operated.
²Terminal number 86 is connected to a switched (+)
power source.
²Terminal number 85 is grounded by the power-
train control module (PCM).
TESTING
(1) Remove relay before testing.
(2) Using an ohmmeter, perform a resistance test
between terminals 85 and 86. Resistance value
(ohms) should be 7565 ohms for resistor equipped
relays.
(3) Connect the ohmmeter between terminals num-
ber 87A and 30. Continuity should be present at this
time.
(4) Connect the ohmmeter between terminals num-
ber 87 and 30. Continuity should not be present at
this time.
(5) Use a set of jumper wires (16 gauge or small-
er). Connect one jumper wire between terminal num-
ber 85 (on the relay) to the ground side (-) of a 12
Volt power source.
(6) Attach the other jumper wire to the positive
side (+) of a 12V power source. Do not connect the
jumper wire to relay at this time.
CAUTION: DO NOT ALLOW THE OHMMETER TO
CONTACT TERMINALS 85 OR 86 DURING THESE
TESTS. DAMAGE TO OHMMETER MAY RESULT.
(7) Attach the other jumper wire (12V +) to termi-
nal number 86. This will activate the relay. Continu-
ity should now be present between terminals number
Fig. 44 Relay Terminals
JFUEL SYSTEM 14 - 47

87 and 30. Continuity should not be present between
terminals number 87A and 30.
(8) Disconnect jumper wires from relay and 12
Volt power source.
If continuity or resistance tests did not pass, re-
place relay. If tests passed, refer to Group 8W, Wir-
ing Diagrams for additional circuit information. Also
refer to the appropriate Powertrain Diagnostic Proce-
dures manual for operation of the DRB scan tool.
STARTER MOTOR RELAY TEST
Refer to Group 8A, Battery/Starting/Charging/Sys-
tem Diagnostics, for starter motor relay testing.
INJECTOR TEST
Disconnect the injector wire connector from the in-
jector. Place an ohmmeter on the injector terminals.
Resistance reading should be approximately 14.5
ohms61.2 ohms at 20ÉC (68ÉF). Proceed to following
Injector Diagnosis chart.
FUEL SYSTEM PRESSURE TEST
Refer to the Fuel Delivery System section of this
group. See Fuel System Pressure Test.
ON-BOARD DIAGNOSTICS (OBD)
The Powertrain Control Module (PCM) has been
programmed to monitor many different circuits of the
fuel injection system. If a problem is sensed in a
monitored circuit often enough to indicate an actual
problem, a Diagnostic Trouble Code (DTC) is stored.
The DTC will be stored in the PCM memory for
eventual display to the service technician. If the
problem is repaired or ceases to exist, the PCM can-
cels the DTC after 51 engine starts.
Certain criteria must be met for a diagnostic trou-
ble code (DTC) to be entered into PCM memory. The
criteria may be a specific range of engine rpm, en-
gine temperature and/or input voltage to the PCM.
It is possible that a DTC for a monitored circuit
may not be entered into memory even though a mal-
function has occurred. This may happen because one
of the DTC criteria for the circuit has not been met.
Example: assume that one of the criteria for the
MAP sensor circuit is that the engine must be oper-
ating between 750 and 2000 rpm to be monitored for
a DTC. If the MAP sensor output circuit shorts to
ground when the engine rpm is above 2400 rpm, a 0
volt input will be seen by the PCM. A DTC will not
be entered into memory because the condition does
not occur within the specified rpm range.
A DTC indicates that the powertrain control mod-
ule (PCM) has recognized an abnormal signal in a
circuit or the system. A DTC may indicate the result
of a failure, but never identify the failed component
directly.There are several operating conditions that the
PCM does not monitor and set a DTC for. Refer to
the following Monitored Circuits and Non-Monitored
Circuits in this section.
MONITORED CIRCUITS
The powertrain control module (PCM) can detect
certain problems in the fuel injection system.
Open or Shorted Circuit- The PCM can deter-
mine if sensor output (which is the input to PCM) is
within proper range. It also determines if the circuit
is open or shorted.
Output Device Current Flow- The PCM senses
whether the output devices are hooked up.
If there is a problem with the circuit, the PCM
senses whether the circuit is open, shorted to ground
(-), or shorted to (+) voltage.
Oxygen Sensor- The PCM can determine if the
oxygen sensor is switching between rich and lean.
This is, once the system has entered Closed Loop. Re-
fer to Open Loop/Closed Loop Modes Of Operation in
the Component Description/System Operation section
for an explanation of Closed (or Open) Loop opera-
tion.
NON-MONITORED CIRCUITS
The PCM does not monitor the following circuits,
systems or conditions that could have malfunctions
that result in driveability problems. A Diagnostic
Trouble Code (DTC) may not be displayed for these
conditions.
Fuel Pressure: Fuel pressure is controlled by the
vacuum assisted fuel pressure regulator. The PCM
cannot detect a clogged fuel pump inlet filter, clogged
in-line fuel filter, or a pinched fuel supply or return
line. However, these could result in a rich or lean
condition causing an oxygen sensor DTC to be stored
in the PCM.
Secondary Ignition Circuit: The PCM cannot
detect an inoperative ignition coil, fouled or worn
spark plugs, ignition cross firing, or open circuited
spark plug cables.
Engine Timing: The PCM cannot detect an incor-
rectly indexed timing chain, camshaft sprocket or
crankshaft sprocket. The PCM also cannot detect an
incorrectly indexed distributor. However, these could
result in a rich or lean condition causing an oxygen
sensor DTC to be stored in the PCM.
Cylinder Compression: The PCM cannot detect
uneven, low, or high engine cylinder compression.
Exhaust System: The PCM cannot detect a
plugged, restricted or leaking exhaust system.
Fuel Injector Malfunctions: The PCM cannot de-
termine if the fuel injector is clogged, or the wrong
injector is installed. However, these could result in a
rich or lean condition causing an oxygen sensor DTC
to be stored in the PCM.
14 - 48 FUEL SYSTEMJ

MULTI-PORT FUEL INJECTION (MFI)ÐCOMPONENT REMOVAL/INSTALLATION
INDEX
page page
Accelerator Pedal and Throttle Cable......... 54
Air Cleaner Housing...................... 54
Air Conditioning (A/C) Clutch Relay........... 54
Air Filter............................... 54
Automatic Shut Down (ASD) Relay........... 54
Brake Switch............................ 54
Camshaft Position Sensor.................. 54
Crankshaft Position Sensor................. 55
Engine Coolant Temperature Sensor.......... 55
Fuel Filter.............................. 55
Fuel Injector............................ 55
Fuel Pump Module....................... 56
Fuel Pump Relay........................ 56
Fuel Rail Assembly....................... 56
Fuel System Pressure Release Procedure...... 56
Fuel Tank Pressure Relief/Rollover Valve...... 56
Fuel Tanks............................. 56Fuel Tubes/Lines/Hoses and Clamps.......... 56
Idle Air Control (IAC) Motor................. 56
Ignition Coil............................. 57
Intake Air Temperature Sensor.............. 54
Intake Manifold.......................... 57
Manifold Absolute Pressure (MAP) Sensor..... 57
Oxygen (O2S) Sensor..................... 57
Park Neutral Switch....................... 58
Power Steering Pressure SwitchÐ2.5L
Engine Only........................... 58
Powertrain Control Module (PCM)............ 58
Quick-Connect Fittings..................... 59
Throttle Body............................ 59
Throttle Position Sensor (TPS).............. 59
Torque Converter Clutch Relay.............. 60
Vehicle Speed Sensor..................... 60
ACCELERATOR PEDAL AND THROTTLE CABLE
Refer to the Accelerator Pedal and Throttle Cable
section of this group for removal/installation proce-
dures.
AIR CONDITIONING (A/C) CLUTCH RELAY
The A/C clutch relay is located in the Power Dis-
tribution Center (PDC) (Figs. 1 or 2). For location of
this relay within the PDC, refer to label on PDC
cover.
AIR CLEANER HOUSING
Refer to Group 25, Emission Control System.
AIR FILTER
Refer to Group 25, Emission Control System.
AUTOMATIC SHUT DOWN (ASD) RELAY
The ASD relay is located in the Power Distribution
Center (Figs. 1 or 2) (PDC). For location of this relay
within the PDC, refer to label on PDC cover.
BRAKE SWITCH
Refer to Group 5, Brakes for removal/installation
procedures.
CAMSHAFT POSITION SENSOR
For removal/installation procedures, refer to Group
8D, Ignition System. See Camshaft Position Sensor.
INTAKE AIR TEMPERATURE SENSOR
The intake manifold air temperature sensor is in-
stalled into the intake manifold plenum (Figs. 3 or
4).
Fig. 1 PDCÐYJ Models
Fig. 2 PDCÐXJ Models
14 - 54 FUEL SYSTEMJ

INSTALLATION
(1) Install the fuel injector(s) into the fuel rail as-
sembly and install retaining clip(s).
(2) Install fuel rail. Refer to Fuel Rail Installation
in this section.
(3) Start engine and check for fuel leaks.
FUEL PUMP MODULE
Refer to the Fuel Delivery System section of this
group for removal/installation procedures.
FUEL PUMP RELAY
The Fuel Pump relay is located in the Power Dis-
tribution Center (PDC) (Figs. 1 or 2). For location of
this relay within the PDC, refer to label on PDC
cover.
FUEL RAIL ASSEMBLY
REMOVAL
WARNING: THE FUEL SYSTEM IS UNDER CON-
STANT FUEL PRESSURE (EVEN WITH THE ENGINE
OFF) OF APPROXIMATELY 131-269 KPA (19-39
PSI). THIS PRESSURE MUST BE RELEASED BE-
FORE SERVICING THE FUEL RAIL.
(1) Remove fuel tank filler tube cap.
(2) Disconnect the negative battery cable from bat-
tery.
(3) Perform the Fuel System Pressure Release Pro-
cedure as described in the Fuel Delivery System sec-
tion of this Group.
(4) Remove and numerically attach a tag (if fuel
injector is not already tagged), the injector harness
connectors. Do this at each injector (Fig. 7).
(5) Disconnect vacuum line from fuel pressure reg-
ulator (Fig. 7).
(6) Disconnect fuel supply line from fuel rail and
the fuel return line from fuel pressure regulator (Fig.7). Refer to Fuel Tubes/Lines/Hoses and Clamps, or
Quick-Connect Fittings. These can both be found in
the Fuel Delivery section of this group.
(7) Remove fuel rail mounting bolts.
On models with automatic transmissions, it may be
necessary to remove automatic transmission throttle
line pressure cable (and bracket). This will aid in fuel
rail assembly removal.
(8) Remove fuel rail by gently rocking until all the
fuel injectors are out of the intake manifold.
INSTALLATION
(1) Position tips of all fuel injectors into the corre-
sponding injector bore in the intake manifold. Seat
injectors into manifold.
(2) Tighten fuel rail mounting bolts to 27 Nzm (20
ft. lbs.) torque.
(3) Connect injector harness connectors to appro-
priate (tagged) injector.
(4) Connect both fuel lines to fuel rail.
(5) Connect vacuum supply line to fuel pressure
regulator.
(6) Install protective cap to pressure test port fit-
ting.
(7) Install fuel tank cap.
(8) Connect negative battery cable to battery.
(9) Start engine and check for fuel leaks.
FUEL SYSTEM PRESSURE RELEASE PROCEDURE
WARNING: THE FUEL SYSTEM IS UNDER A CON-
STANT PRESSURE (EVEN WITH THE ENGINE OFF)
OF APPROXIMATELY 100 KPA (14.5 PSI). BEFORE
SERVICING THE FUEL PUMP, FUEL LINES, FUEL
FILTER OR FUEL INJECTOR, THE FUEL SYSTEM
PRESSURE MUST BE RELEASED.
Refer to the Fuel Delivery System section of this
group. See Fuel Pressure Release procedure.
FUEL TANKS
Refer to the Fuel Tank section of this group for re-
moval/installation procedures.
FUEL TANK PRESSURE RELIEF/ROLLOVER VALVE
Refer to the Fuel Tank section of this group for re-
moval/installation procedures.
FUEL TUBES/LINES/HOSES AND CLAMPS
Refer to the Fuel Delivery System section of this
group for removal/installation procedures. Also refer
to Quick-Connect Fittings in the Fuel Delivery sec-
tion of this group.
IDLE AIR CONTROL (IAC) MOTOR
The IAC motor is mounted to the throttle body ad-
jacent to the throttle position sensor (Fig. 8).
Fig. 7 Fuel Injector HarnessÐTypical
14 - 56 FUEL SYSTEMJ

FUEL SYSTEM
CONTENTS
page page
ACCELERATOR PEDAL AND THROTTLE CABLE... 16
FUEL DELIVERY SYSTEM................. 2
FUEL TANKS........................... 12
GENERAL INFORMATION.................. 1
MULTI-PORT FUEL INJECTION (MFI)ÐCOMPO-
NENT DESCRIPTION/SYSTEM OPERATION . 17MULTI-PORT FUEL INJECTION (MFI)Ð
COMPONENT REMOVAL/INSTALLATION . . . 54
MULTI-PORT FUEL INJECTION (MFI)Ð
GENERAL DIAGNOSIS.................. 32
SPECIFICATIONS....................... 62
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.
TheFuel Systemconsists of: the fuel tank, an
electric (fuel tank mounted) fuel pump and a fuel fil-
ter. It also consists of fuel tubes/lines/hoses, vacuum
hoses, throttle body and fuel injectors.
TheFuel Delivery Systemconsists of: the electric
fuel pump, fuel filter, fuel tubes/lines/hoses, fuel rail,
fuel injectors and fuel pressure regulator.
AFuel Return Systemis used on all vehicles.
The system consists of: the fuel tubes/lines/hoses that
route fuel back to the fuel tank.
TheFuel Tank Assemblyconsists 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
Your vehicle was designed to meet all emission reg-
ulations 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 gasolinecan cause problems such
as hard starting, stalling and stumble. If you experi-
ence these problems, use another brand of gasoline
before considering service for the vehicle.
GASOLINE/OXYGENATE BLENDS
Some fuel suppliers blend unleaded gasoline with
materials that contain oxygen such as alcohol, MTBE
and ETBE. The type and amount of oxygenate used
in the blend is important. The following are generally
used in gasoline blends:
ETHANOL
Ethanol (Ethyl or Grain Alcohol) properly blended,
is used as a mixture of 10 percent ethanol and 90
percent gasoline.Gasoline with ethanol may be
used in your vehicle.
METHANOL
CAUTION: DO NOT USE GASOLINES CONTAINING
METHANOL.Use of methanol/gasoline blends may re-
sult in starting and driveability problems. In addition,
damage may be done to critical fuel system compo-
nents.
Methanol (Methyl or Wood Alcohol) is used in a va-
riety of concentrations blended with unleaded gaso-
JFUEL SYSTEM 14 - 1

line. You may encounter fuels containing 3 percent
or more methanol along with other alcohols called co-
solvents.
Problems that are the result of using methanol/gas-
oline blends are not the responsibility of Chrysler
Corporation. They may not be covered by the vehicle
warranty.
MTBE/ETBE
Gasoline and MTBE (Methyl Tertiary Butyl Ether)
blends are a mixture of unleaded gasoline and up to
15 percent MTBE. Gasoline and ETBE (Ethyl Ter-
tiary Butyl Ether) are blends of gasoline and up to
17 percent ETBE. Gasoline blended with MTBE or
ETBE may be used in your vehicle.CLEAN AIR GASOLINE
Many gasolines are now being blended that con-
tribute to cleaner air, especially in those areas of the
country where air pollution levels are high. These
new blends provide a cleaner burning fuel and some
are referred to asReformulated Gasoline.
In areas of the country where carbon monoxide lev-
els are high, gasolines are being treated with oxy-
genated materials such as MTBE, ETBE and
ethanol.
Chrysler Corporation supports these efforts toward
cleaner air and recommends that you use these gas-
olines as they become available.
FUEL DELIVERY SYSTEM
INDEX
page page
Fuel Filter............................... 8
Fuel Pressure Leak Down Test............... 7
Fuel Pressure Release Procedure............. 5
Fuel Pump Capacity Test................... 7
Fuel Pump Electrical Control................. 5Fuel Pump Module........................ 2
Fuel System Pressure Test.................. 5
Fuel Tubes/Lines/Hoses and Clamps........... 9
Quick-Connect Fittings..................... 9
FUEL PUMP MODULE
The fuel pump module is installed in the top of the
fuel tank. The fuel pump module contains the follow-
ing components:
²Electric fuel pump
²Fuel pump reservoir
²In-tank fuel filter
²Fuel gauge sending unit
²Fuel supply and return tube connections
The fuel pump used on all vehicles is a gear/rotor
type pump. It is driven by a permanent magnet 12
volt electric motor that is immersed in the fuel tank.
The electrical pump is integral with the fuel sender
unit. The pump/sender assembly is installed inside
the fuel tank.
The fuel pump has a check valve at the outlet end
that consists of a ball held against a seat by force ap-
plied from a spring. When the pump is operating,
fuel pressure overcomes spring pressure and forces
the ball off its seat, allowing fuel to flow. When the
pump is not operating, spring pressure forces the ball
back against the seat preventing fuel backflow
through the pump.
Fuel system pressure is maintained at approxi-
mately 214 kPa (31 psi). This is when the pump is
operating and vacuum is supplied to the fuel pres-
sure regulator. If vacuum is not supplied to the pres-
sure regulator, fuel pressure will be approximately
55-69 kPa (8-10 psi) higher. This may be due to a
broken or clogged vacuum line. When the fuel pumpis not operating, system fuel pressure of 131-269 kPa
(19-39 psi) is maintained. This is done by the fuel
pump outlet check valve and the vacuum assisted
fuel pressure regulator.
REMOVALÐXJ MODELS
The fuel pump/gauge sender unit assembly can be
removed from the fuel tank without removing the
tank from the vehicle.
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. REFER TO THE FUEL PRESSURE RE-
LEASE PROCEDURE IN THIS GROUP.
WARNING: EXTINGUISH ALL TOBACCO SMOKING
PRODUCTS BEFORE SERVICING THE FUEL SYS-
TEM. KEEP OPEN FLAME AWAY FROM FUEL SYS-
TEM COMPONENTS.
(1) Remove fuel filler cap. Perform the Fuel Pres-
sure Release Procedure as outlined in this group.
(2) Disconnect negative battery cable.
(3) Using an approved portable gasoline siphon/
storage tank, drain fuel tank until fuel level is below
one quarter (1/4) full.
(4) Raise and support vehicle.
14 - 2 FUEL SYSTEMJ

WARNING: WRAP SHOP TOWELS AROUND FUEL
HOSES TO ABSORB ANY FUEL SPILLAGE DURING
FUEL TANK REMOVAL.
(5) Disconnect fuel vent supply and return tubes
from fittings on fuel pump module.
(6) Disconnect fuel pump module electrical harness
connector from main harness.
(7) Using a brass punch and hammer, remove fuel
pump module lock ring by carefully tapping it coun-
terclockwise (Fig. 1).
(8) Remove fuel pump module and O-ring seal.
Discard old O-ring and fuel pump module inlet filter.
DISASSEMBLYÐXJ MODELS
(1) Remove and discard fuel pump inlet filter.
The wire terminals to the fuel pump motor are dif-
ferent in size and cannot be connected to the wrong
terminal.
(2) Disconnect fuel pump terminal wires.
(3) Remove fuel pump outlet hose and clamp. Re-
place the hose if it shows any signs of fatigue or fail-
ure.
(4) Remove fuel pump top mounting bracket nut.
Remove fuel pump (Fig. 2).
ASSEMBLYÐXJ MODELS
Whenever the fuel pump is replaced, the fuel pump
inlet filter (sock) must also be replaced.
(1) Place fuel pump top mounting bracket over top
of pump.
(2) Position fuel pump into lower bracket. Slide
stud of top bracket through hole in fuel pump side
bracket. Tighten fuel pump top mounting nut.
(3) Install new fuel pump outlet hose. Secure with
new clamps.
(4) Connect wire terminals to motor.
(5) Install new fuel pump inlet filter.
INSTALLATIONÐXJ MODELS
Whenever the fuel pump is replaced, the fuel
pump inlet filter must also be replaced.
(1) Install new fuel pump inlet filter onto fuel
pump.
(2) Install fuel pump module assembly and new O-
ring seal. The rubber stopper on the end of the fuel
return tube of the assembly must be inserted into the
cup in the fuel tank reservoir (Fig. 3).
Fig. 1 Removing Lock RingÐXJ ModelsÐTypical
Fig. 2 Fuel Pump ModuleÐXJ
ModelsÐDisassemble/Assemble
Fig. 3 Fuel Pump ModuleÐXJ ModelsÐInstallation
JFUEL SYSTEM 14 - 3

(3) Using a brass punch and a hammer, install
lock ring. Carefully tap lock ring clockwise until it
seats against stop on fuel tank.
(4) Connect fuel supply and return hoses to fittings
on fuel pump module. Tighten hose clamps.
(5) Connect fuel pump module electrical harness
connector to main harness connector.
(6) Lower vehicle.
(7) Fill fuel tank. Install fuel tank cap.
(8) Connect negative battery cable.
(9) Start vehicle and inspect for leaks.
REMOVALÐYJ MODELS
The fuel tank must be removed to remove the fuel
pump module.
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. REFER TO THE FUEL PRESSURE RE-
LEASE PROCEDURE IN THIS GROUP.
WARNING: EXTINGUISH ALL TOBACCO SMOKING
PRODUCTS BEFORE SERVICING THE FUEL SYS-
TEM. KEEP OPEN FLAME AWAY FROM FUEL SYS-
TEM COMPONENTS.
(1) Remove negative battery cable.
(2) Remove fuel filler cap. Perform the Fuel Pres-
sure Release Procedure as outlined in this group.
(3) Remove fuel tank. Refer to Fuel Tank Remov-
alÐYJ Models.
(4) Remove fuel pump module assembly.
(5) Remove mounting screws. Lift assembly and
gasket out of fuel tank. Discard old gasket (Fig. 4).
(6) Remove and discard fuel pump inlet filter.DISASSEMBLYÐYJ MODELS
(1) Remove and discard fuel pump inlet filter (Fig.
5).
The wire terminals to the fuel pump motor are dif-
ferent in size and cannot be connected to the wrong
terminal.
(2) Disconnect fuel pump terminal wires from
pump.
(3) Remove fuel pump outlet hose and clamp (Fig.
6). Replace the hose if it shows any signs of fatigue
or failure.
(4) Remove fuel pump top mounting bracket nut
(Fig. 6). Remove fuel pump.
ASSEMBLYÐYJ MODELS
Whenever the fuel pump is replaced, the fuel pump
inlet filter (sock) must also be replaced.
(1) Place fuel pump top mounting bracket over top
of pump.
(2) Position fuel pump into lower bracket. Slide
stud of top bracket through hole in fuel pump side
bracket. Tighten fuel pump top mounting nut.
Fig. 4 Fuel Pump ModuleÐRemove/InstallÐYJ
Models
Fig. 5 Fuel Pump ModuleÐYJ Models
Fig. 6 Fuel Pump Removal/InstallationÐYJ Models
14 - 4 FUEL SYSTEMJ