fuel filter CHEVROLET DYNASTY 1993 User Guide
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Page 1580 of 2438

CAUTION: Make sure clutch cable has been discon-
nected. (20) Remove front engine mount screw and nut.
(21) Remove manual transmission damper.
(22) Remove left insulator through bolt from inside
wheelhouse or insulator bracket to transmission
screws. (23) Remove engine from vehicle.
INSTALLATION
(1) Install hoist to the engine and lower engine
into the engine compartment. SEE: ENGINE MOUNT RUBBER INSULATORS,
THIS GROUP. (2) Align engine mounts and install but do not
tighten until all mounting bolts have been installed.
(3) Install transmission case to cylinder block
mounting screws. Tighten to 95 N Im (70 ft. lbs.)
torque. (4) Remove engine hoist and transmission holding
fixture. (5) Install ground strap.
(6) Install right inner splash shield.
(7) Connect starter. See Electrical Group 8 for in-
stallation. (8) Connect exhaust system. See Exhaust Systems
Group 11 for installation. (9) Manual Transmission: Install transmission
case lower cover. Automatic Transmission: Remove C clamp from
torque converter housing. Align flexplate to torque
converter and install mounting screws. Tighten to 75
N Im (55 ft. lbs.) torque.
(10) Manual Transmission: Connect clutch cable.
See Clutch Group 6. (11) Install power steering pump. Refer to Cooling
System Group 7, Accessory Drive Section for belt
tension adjustment. (12) Connect fuel line, heater hose, and accelerator
cable. (13) Connect all electrical connections and har-
nesses at throttle body and engine. (14) Install oil filter. Fill engine crankcase with
proper oil to correct level. (15) Install air conditioning compressor (if
equipped). See Heater and Air Conditioning, Group
24 for installation. (16) Install air cleaner and hoses.
(17) Install radiator and shroud assembly . Install
radiator hoses. Fill cooling system. See Cooling Sys-
tem Group 7 for filling procedure. (18) Install hood.
(19) Connect battery.
(20) Start engine and run until operating temper-
ature is reached. (21) Adjust transmission linkage, if necessary.
SOLID MOUNT COMPRESSOR BRACKET SERVICE
When service procedures require solid mount
bracket removal and installation for example: cylin-
der head removal, etc., it is important that bracket
fasteners numbered 1 through 7 (Fig. 4) be removed
and installed in sequence, as instructed in Remove
and Install.
ACCESSORIES REMOVAL
(1) Remove (and install/adjust) belts,see Accessory
Drive Belts in Cooling System,Group 7. (2) Remove air conditioning compressor (in vehicle
with lines and set aside) (Fig. 6). (3) Remove generator pivot bolt and remove gener-
ator (in vehicle: turn wiring side up and disconnect,
then rotate generator, pulley end towards engine and
remove). (4) Remove air conditioner compressor belt idler.
SOLID MOUNT BRACKETÐREMOVAL (FIG. 4)
(1) Remove right engine mount yoke screw (see
Engine Remove Fig. 3) securing engine mount sup-
port strut to engine mount bracket. (2) Remove five side mounting bolts #1, #4 , #5,
#6, and #7 (Fig. 4). (3) Remove front mounting nut, #2, and remove
front bolt #3*. (4) Remove front mounting bolt and strut, rotate
solid mount bracket away from engine and slide
bracket on stud until #2 nut mounting stud until
free. Remove spacer from stud.
SOLID MOUNT BRACKETÐINSTALLATION
(1) Put spacer onto stud, then install bracket on
front (#2 nut) mounting stud and slide bracket over
timing belt cover into position. (2) Loosen assembly bracket to engine fasteners
(numbered #1 through #7 in Fig. 6). (3)
CAUTION: Fasteners MUST BE TIGHTENED IN SE-
QUENCE and to specified torque as follows :
² First Bolt #1 to 3.3 N Im (30 in. lbs.)
² Second Nut #2 and Bolt #3 to 54 N Im (40 ft. lbs.).
² Third Bolts #1 (second tightening) #4 and #5 to
54 N Im (40 ft. lbs.).
² Fourth Bolts #6 and #7 to 54 N Im (40 ft. lbs.).
(4) Install generator and compressor. Tighten com-
pressor mounting bracket bolts to 54 N Im (40 ft.
lbs.).
SOLID MOUNT COMPRESSOR BRACKET SERVICEÐTURBO III ENGINE
REMOVAL
(1) Disconnect negative battery cable
9 - 14 2.2/2.5L ENGINE Ä
Page 1702 of 2438

for diagnostic and service procedures on the air control
valve and temperature sensor located in the air
cleaner.
INTAKE AND EXHAUST MANIFOLDS SERVICEÐTBI
ENGINE
Intake and exhaust manifolds use a one piece gasket.
Service procedures requiring removal and installation
( of either ) must include both manifolds.
FUEL SYSTEM PRESSURE RELEASE PROCE- DURE
The Fuel System is under a constant pressure
of at least 265 kPa (39 psi). Before servicing the
fuel pump, fuel lines, fuel filter, throttle body or
fuel injector, the fuel system pressure must be
released. (a) Loosen fuel filler cap to release fuel tank pres-
sure. (b) Disconnect injector wiring harness from engine
harness. (c) Connect a jumper wire to ground terminal
Number 1 of the injector harness (Fig. 2) to engine
ground. (d) Connect a jumper wire to the positive terminal
Number 2 of the injector harness (Fig. 2) and touch
the battery positive post for no longer than 5 seconds.
This releases system pressure. (e) Remove jumper wires.
(f) Continue fuel system service.
REMOVAL
(1) Perform fuel system pressure release procedure
before attempting any repairs. (2) Disconnect negative battery cable. Drain cool-
ing system. Refer to Cooling System, Group 7 for pro-
cedure. (3) Remove air cleaner and disconnect all vacuum
lines, electrical wiring and fuel lines from throttle
body. (4) Remove throttle linkage.
(5) Loosen power steering pump and remove belt.
(6) Remove power brake vacuum hose from intake
manifold. (7) Disconnect EGR tube from intake manifold and
remove water hoses from water crossover. (8) Raise vehicle and remove exhaust pipe from
manifold. (9) Remove power steering pump assembly and set
aside. (10) Remove intake manifold retaining screws
(Fig. 3). (11) Lower vehicle and remove intake manifold.
(12) Remove exhaust manifold retaining nuts (Fig.
3). (13) Remove exhaust manifold.
Fig. 2 Injector Harness Connector
Fig. 3 Intake and Exhaust Manifold Attaching PointsÐ2.2/2.5L Engines
Fig. 1 Air HeaterÐTBI Engine
11 - 6 EXHAUST SYSTEM AND INTAKE MANIFOLD Ä
Page 1705 of 2438

EXHAUST MANIFOLD
REMOVAL (1) Disconnect exhaust pipe from manifold articu-
late joint. (2) Disconnect the heated oxygen sensor electrical
connection. (3) Remove 8 exhaust manifold retaining nuts and
remove exhaust manifold (Fig. 9).
CLEANING AND INSPECTION
(1) Discard gasket and clean all gasket surfaces of
manifolds and cylinder head. (2) Test gasket surfaces for flatness with straight
edge. Surface must be flat within 0.15 mm per 300
mm (.006 in. per foot) of manifold length. (3) Inspect manifolds for cracks or distortion.
EXHAUST MANIFOLD
INSTALLATION
(1) Install new two-sided grafoil or equivalent in-
take/exhaust manifold gasket. DO NOT APPLY
SEALER. (2) Set exhaust manifold in place. Install and
tighten retaining nuts, starting at center and pro-
gressing outward in both directions to 23 N Im (200
in. lbs.) torque. Repeat this procedure until all nuts
are at specified torque.
INTAKE MANIFOLD
INSTALLATION
(1) Position intake manifold, install, and tighten 8
retaining screws starting at center and progressing
outward in both directions to 23 N Im (200 in. lbs.)
torque. Repeat this procedure until all screws are at
specified torque (Fig. 9). (2) Install PCV vacuum harness and vacuum vapor
harness (Fig. 8). (3) Connect vacuum hose from fuel pressure regu-
lator. (4) Connect fuel injector wiring connector (Fig. 8).
(5) Close fuel tube clip around fuel tubes and in-
stall fastener. (6) Lubricate the ends of the chassis fuel tubes
with 30 wt oil. Connect fuel supply and return hoses
to chassis fuel tube assembly. pull back on the quick
connect fitting to ensure complete insertion. (Refer to
Fuel Hoses, Clamps and Quick Connect Fittings in
Group 14 Fuel Systems). (7) Connect automatic idle speed (AIS) motor and
throttle position sensor (TPS) wiring connectors (Fig.
7). (8) Connect accelerator and speed control cables.
Install brake booster vacuum supply hoses. (9) Reconnect negative battery cable.
(10) Install air cleaner hose to throttle body assem-
bly (Fig. 6). (11) With the DRBII Scan Tool use ASD Fuel Sys-
tem Test to pressurize system to check for leaks.
CAUTION: When using the ASD Fuel System Test,
the Auto Shutdown (ASD) relay will remain ener-
gized for 7 minutes or until the ignition switch is
turned to the OFF position, or Stop All Test is se-
lected.
INTAKE/EXHAUST MANIFOLDS AND
TURBOCHARGER SERVICEÐTURBO III ENGINE
INTAKE MANIFOLD
REMOVAL
(1) Perform fuel system pressure release procedure
before attempting any repairs. (2) Disconnect negative battery cable. Drain cool-
ing system. Refer to Cooling System, Group 7. (3) Remove fresh air duct from air filter housing.
Remove inlet hose from the intercooler (Fig. 1). (4) Remove radiator hose to cylinder head (Fig. 2).
(5) Remove DIS Ignition Coils from intake mani-
fold (Fig. 3). (6) Remove accelerator and speed control cables
(Fig. 4).
Fig. 9 Intake and Exhaust Manifolds Attaching Points
Ä EXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 9
Page 1707 of 2438

(3) Inspect quick connect fittings for damage, re-
place if necessary Refer to Fuel System, Group 14 for
procedure. Lube tube with clean 30w engine oil, Con-
nect fuel supply and return hoses to chassis tube as-
sembly. Check connection by pulling on connector to
insure it locked into position (Fig. 9). (4) Connect Fuel Injector (Fig. 8), and Charge
Temperature Sensor wiring connectors (Fig. 7).
INTAKE MANIFOLD
(5) Connect Automatic Idle Speed (AIS) and Throt-
tle Position Sensor (TPS) wiring connectors (Fig. 6). (6) Connect vacuum hoses to throttle body (Fig. 5).
(7) Install intercooler to throttle body hose and
clamp. Torque clamp to 3 N Im (30 in. lbs.) (Fig. 5). (8) Connect accelerator and speed control cables
(Fig. 4). (9) Install DIS ignition coil pack. Tighten fasteners
to 12 N Im (105 in. lbs.) torque (Fig. 3).
(10) Install upper radiator hose and spring clamps
(Fig. 2). Fill cooling system, Refer to Cooling System,
Group 7. (11) Install fresh air duct to air filter housing. In-
stall inlet hose assembly to Intercooler. Tighten
clamp to 3 N Im (30 in. lbs.) torque (Fig. 1).
(12) Connect negative battery cable.
(13) With the DRBII Scan Tool use ASD Fuel Sys-
tem Test to pressurize system to check for leaks.
Fig. 5 Intercooler to Throttle Body Hose
Fig. 6 Automatic Idle Speed (AIS) Motor and
Throttle Position Sensor (TPS) Wiring Connectors
Fig. 7 Intake Manifold Electrical and Vacuum Hose Connections
Fig. 8 Camshaft Sensor and Fuel Injectors WiringConnectors
Ä EXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 11
Page 1710 of 2438

The exhaust manifolds are made of ductile cast
iron with the front bank and rear bank independent
of each other. The exhaust from the front bank ex-
haust manifold is led through on exhaust crossover
pipe to be combined with the rear bank exhaust at
the exhaust outlet to the exhaust pipe (Fig. 2).
INTAKE PLENUM/MANIFOLD
REMOVAL
(1) Perform fuel system pressure release procedure
(before attempting any repairs). (2) Disconnect negative battery cable. Drain cooling
system. See Cooling System, Group 7. (3) Remove air cleaner to throttle body hose (Fig. 3).
FUEL SYSTEM PRESSURE RELEASE PROCE-DURE
The MPI fuel system is under a constant pres-
sure of about 330 kPa (48 psi). Before servicing
the fuel pump, fuel lines, fuel filter, throttle body
or fuel injector, the fuel system pressure must be
released .
(a) Loosen fuel filler cap to release fuel tank pres-
sure. (b) Disconnect injector wiring harness from engine
harness. (c) Connect a jumper wire to ground terminal
Number 1 of the injector harness (Fig. 1) to engine
ground. (d) Connect a jumper wire to the positive terminal
Number 2 of the injector harness (Fig. 1) and touch
the battery positive post for no longer than 5 seconds.
This releases system pressure.
Fig. 1 Injector Harness Connector
Fig. 2 Intake and Exhaust ManifoldsÐ 3.0L Engine
11 - 14 EXHAUST SYSTEM AND INTAKE MANIFOLD Ä
Page 1715 of 2438

(2) Attach exhaust pipe to exhaust manifold and
tighten shoulder bolt to 28 N Im (250 in. lbs.)
(3) Attach crossover pipe to exhaust manifold and
tighten bolt to 69 N Im (51 ft. lbs.)
(4) Connect heated oxygen sensor lead (Fig. 18).
(5) Install front exhaust manifold and attach ex-
haust crossover. (6) Install front manifold heat shield and tighten
attaching screws to 15 N Im (130 in. lbs.) (Fig. 2).
INTAKE/EXHAUST MANIFOLD SERVICEÐ3.3/3.8L
ENGINES
INTAKE MANIFOLD
REMOVAL
(1) Perform fuel system pressure release procedure,
Before attempting any repairs. (2) Disconnect negative battery cable. Drain cool-
ing system. Refer to Cooling System, Group 7.
FUEL SYSTEM PRESSURE RELEASE PROCE- DURE
The MPI fuel system is under a constant pressure
of about 330 kPa (48 psi). Before servicing the fuel
pump, fuel lines, fuel filter, throttle body or fuel
injector, the fuel system pressure must be released.
(a) Loosen fuel filler cap to release fuel tank pres-
sure. (b) Disconnect injector wiring harness from engine
harness.
(c) Connect a jumper wire to ground terminal Num-
ber 1 of the injector harness (Fig. 1) to engine ground.
(d) Connect a jumper wire to the positive terminal
Number 2 of the injector harness (Fig. 1) and touch
the battery positive post for no longer than 5 seconds.
This releases system pressure. (e) Remove jumper wires.
(f) Continue fuel system service.
(3) Remove air cleaner to throttle body hose assem-
bly (Fig. 2).
Fig. 20 Check Exhaust Manifold Mounting Surface
Fig. 21 Identify Exhaust Manifold Gaskets
Fig. 1 Injector Harness Connectors
Fig. 2 Throttle Body AssemblyÐ3.3/3.8L Engines
Ä EXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 19
Page 1741 of 2438

FUEL SYSTEMS
CONTENTS
page page
2.2L TURBO III MULTI-PORT FUEL INJECTIONÐ GENERAL DIAGNOSIS ................. 95
2.2L TURBO III MULTI-PORT FUEL INJECTIONÐ ON-BOARD DIAGNOSTICS ............. 100
2.2L TURBO III MULTI-PORT FUEL INJECTIONÐ SERVICE PROCEDURES ............... 107
2.2L TURBO III MULTI-PORT FUEL INJECTIONÐ SYSTEM OPERATION .................. 83
2.2L/2.5L SINGLE POINT FUEL INJECTIONÐ GENERAL DIAGNOSIS .................. 35
2.2L/2.5L SINGLE POINT FUEL INJECTIONÐ ON-BOARD DIAGNOSTICS .............. 41
2.2L/2.5L SINGLE POINT FUEL INJECTIONÐ SERVICE PROCEDURES ................ 48
2.2L/2.5L SINGLE POINT FUEL INJECTIONÐ SYSTEM OPERATION .................. 24
2.5L FLEXIBLE FUEL MULTI-PORT FUEL INJECTIONÐGENERAL DIAGNOSIS ....... 66
2.5L FLEXIBLE FUEL MULTI-PORT FUEL INJECTIONÐON-BOARD DIAGNOSTICS . . . 70
2.5L FLEXIBLE FUEL MULTI-PORT FUEL INJECTIONÐSERVICE PROCEDURES ..... 77
2.5L FLEXIBLE FUEL MULTI-PORT FUEL INJECTIONÐSYSTEM OPERATION ....... 55 3.0L MULTI-PORT FUEL INJECTIONÐ
GENERAL DIAGNOSIS ................. 125
3.0L MULTI-PORT FUEL INJECTIONÐ ON-BOARD DIAGNOSTICS ............. 130
3.0L MULTI-PORT FUEL INJECTIONÐ SERVICE PROCEDURES ............... 138
3.0L MULTI-PORT FUEL INJECTIONÐ SYSTEM OPERATION ................. 113
3.3L AND 3.8L MULTI-PORT FUEL INJECTIONÐ GENERAL DIAGNOSIS ................. 157
3.3L AND 3.8L MULTI-PORT FUEL INJECTIONÐ ON-BOARD DIAGNOSTICS ............. 162
3.3L AND 3.8L MULTI-PORT FUEL INJECTIONÐ SERVICE PROCEDURES ............... 169
3.3L AND 3.8L MULTI-PORT FUEL INJECTIONÐ SYSTEM OPERATION ................. 145
ACCELERATOR PEDAL AND THROTTLE CABLE .............................. 21
FUEL DELIVERY SYSTEM ................. 3
FUEL TANKS .......................... 14
GENERAL INFORMATION .................. 1
SPECIFICATIONS ...................... 178
GENERAL INFORMATION
Throughout this group, references are made to a
particular vehicle by letter designation. A chart
showing the breakdown of these designations is in-
cluded in the Introduction Section at the front of this
service manual. The Fuel System consists of the fuel tank, fuel
pump, fuel filter, throttle body, fuel injectors, fuel
tubes and vacuum tubes. The Fuel Delivery System consists of the fuel
pump, fuel filter, fuel lines and fuel hoses. The Fuel Tank Assembly consists of the fuel tank,
filler tube, a fuel gauge sending unit assembly and a
pressure-vacuum filler cap. Also, the Evaporation Control System is part of the
fuel system. The evaporation control system is de-
signed to reduce the emission of fuel vapor into the
atmosphere. The description and function of the Evaporation
Control System is found in Group 25 of this manual.FUEL REQUIREMENTS
Your vehicle was designed to meet all emission
regulations and provide excellent fuel economy when
using high quality unleaded gasoline.
VEHICLES WITHOUT TURBOCHARGED ENGINES
Use unleaded gasoline having a minimum octane
rating of 87.
VEHICLES WITH TURBOCHARGED ENGINESÐEXCEPT 16 VALVE 2.2L ENGINES
These vehicles will operate satisfactorily on both
regular unleaded gasoline having a minimum octane
rating or 87, and premium unleaded gasoline having
a minimum octane rating of 91. The use of premium
unleaded gasoline will improve performance.
VEHICLES WITH 2.2L 16 VALVE ENGINES
The use of premium unleaded gasoline having a
minimum octane of 91 is recommended. If premium
unleaded is not available, then unleaded gasoline
Ä FUEL SYSTEMS 14 - 1
Page 1743 of 2438

FUEL DELIVERY SYSTEM INDEX
page page
Chassis Fuel Tubes ...................... 11
Flexible Fuel Components ................... 3
Fuel FilterÐAll Vehicles .................... 9
Fuel Hoses, Clamps, and Quick Connect Fittings . 10
Fuel Pump Assembly ...................... 5
Fuel Pump Module Installation ............... 9
Fuel Pump Module Removal ................. 8
Fuel Pump Pressure TestÐ2.2L/2.5L TBI and 3.0L MPI Engines ........................... 7
Fuel Pump Pressure TestÐAll Except 2.2L/2.5L TBI and 3.0L MPI ....................... 6
Fuel Pump Strainer Service .................. 9 Fuel System Pressure
...................... 6
Fuel System Pressure Release ProcedureÐ 2.2L/2.5L TBI ........................... 4
Fuel System Pressure Release ProcedureÐ3.0L . . 5
Fuel System Pressure Release ProcedureÐExcept 2.2L/2.5L TBI and 3.0L ................... 4
General Information ........................ 3
Identifying Flexible Fuel Components .......... 3
Mechanical Malfunctions .................... 8
Methanol Concentration SensorÐFlexible Fuel AA-Body .............................. 4
Service Precautions for Flexible Fuel Vehicles .... 3
GENERAL INFORMATION
Beginning this model year, Chrysler began produc-
ing AA-Body vehicles designed to operate on a mix-
ture of gasoline and methanol. These automobiles are
referred to as Flexible Fuel vehicles. Flexible fuel vehicles can operate on a mixture of
up to 85 percent methanol, 15 percent unleaded gas-
oline. These vehicles also operate on mixtures con-
taining a lower percentage of methanol or just pure
unleaded gasoline. In many cases, the procedures for servicing flexible
fuel components is identical to gasoline only compo-
nents. Refer to the particular Service Procedure in
this section. If the service procedure for flexible fuel
component differs from a gasoline only component,
the title of each service procedure identifies the ap-
plication.
SERVICE PRECAUTIONS FOR FLEXIBLE FUEL
VEHICLES
Methanol is more toxic than gasoline. Always re-
lease fuel system pressure before servicing fuel sys-
tem components and wear methanol resistant gloves
and eye protection. Avoid breathing methanol vapors or ingesting
methanol. Headaches, dizziness and even uncon-
sciousness could result from breathing these vapors.
Serious injury, blindness and even death could result
from ingesting methanol. Methanol vapors are extremely flammable and can
travel along the ground. Service vehicles in well ven-
tilated areas and avoid ignition sources. Never
smoke while servicing the vehicle. Do not allow methanol to contact skin. Prolonged
contact with methanol can cause dry skin or an al-
lergic skin reaction. Also, prolonged contact could re-
sult in absorption through the skin.
IDENTIFYING FLEXIBLE FUEL COMPONENTS
Flexible Fuel vehicles have unique methanol com-
patible fuel system components. Chrysler identifies
methanol compatible components that could be phys-
ically interchanged with gasoline only parts by color-
ing them green or applying a green label or tag to
them. Even though they may appear physically iden-
tical, components for gasoline only vehicles must not
be used on flexible fuel vehicles.
FLEXIBLE FUEL COMPONENTS
Flexible fuel AA-body vehicles uses many unique
fuel system components. The unique parts are green
in appearance or have a green tag or label attached
to them. While components used on gasoline only ve-
hicles may look similar or identical, they cannot be
used on flexible fuel vehicles. When servicing a com-
ponent, always use an original equipment or equiva-
lent flexible fuel replacement. The fuel system of flexible fuel AA-body vehicles
have the following unique components.
² Fuel pump module
² Fuel level sensor
² Fuel gauge (gauge cluster).
² Fuel tank
² Fuel pressure regulator (including O-rings)
² Fuel rail
² Fuel injectors (including O-rings)
² Fuel tubes
² Fuel filter
² EVAP canister
² Fuel filler cap
² Fuel filler tube
² Pressure relief/Rollover valve
² All fuel system and emission system hoses and
tubes
Ä FUEL SYSTEMS 14 - 3
Page 1744 of 2438

INSTRUMENT PANEL CLUSTER IDENTIFICATIONÐFLEXIBLE FUEL AA-BODY
Flexible fuel A-Body vehicles use a unique gauge
cluster. To identify the cluster, remove it from the
instrument panel and check the number on the tag
on the top. If the part number matches the number
in the parts book for flexible fuel A-bodies, the vehi-
cle was built with the correct cluster. Refer to Group
8E, Instrument Panel and Gauges, for cluster re-
moval and installation.
METHANOL CONCENTRATION SENSORÐFLEXIBLE
FUEL AA-BODY
The methanol concentration sensor contains a mi-
croprocessor that determines the percentage of gaso-
line and methanol in the fuel system. From the
methanol concentration sensor input, the powertrain
control module (PCM) determines the amount of
methanol in the fuel. The vehicle can operate on a
mixtures up to 85 percent methanol, 15 percent gas-
oline. The methanol concentration sensor output voltages
varies with the percent of methanol in the fuel sys-
tem. The sensor output voltage (input for PCM)
ranges from 0.5 volts for pure gasoline to 4.75 volts
for 85 percent methanol. For two seconds at key ON
when the operator starts the vehicle, the sensor cal-
ibrates the PCM. During the calibration period the
sensor sends 4.45 volts to the PCM as a correction
factor. The methanol concentration sensor has a built-in
shutdown capability. If the sensor shuts down, it de-
faults to the previous learned value (output voltage
based on methanol percentage of fuel). The methanol concentration sensor attaches to a
bracket at the rear of the fuel tank, next to the fuel
filler tube (Fig. 1).
REMOVAL
WARNING: RELEASE FUEL SYSTEM PRESSURE
BEFORE SERVICING FUEL SYSTEM COMPONENTS.
WHEN SERVICING FLEXIBLE FUEL VEHICLES,
WEAR METHANOL RESISTANT GLOVES AND EYE
PROTECTION AND AVOID BREATHING FUMES. DO
NOT ALLOW METHANOL/GASOLINE MIXTURES TO
CONTACT SKIN. SERVICE VEHICLES IN WELL VEN-
TILATED AREAS AND AVOID IGNITION SOURCES.
NEVER SMOKE WHILE SERVICING THE VEHICLE.
Quick connect fittings attach the fuel tubes to the
methanol concentration sensor (Fig. 1) (1) Release fuel system pressure. Refer to the Fuel
System Pressure Release Procedure. (2) Disconnect the fuel tubes from sensor. Refer to
Quick Connect Fittings in this section. (3) Disconnect electrical connector from sensor.
(4) Remove mounting nuts.
INSTALLATION
(1) Place sensor on bracket. Tighten mounting nut.
(2) Attach electrical connector to sensor.
(3) Connect fuel tubes to sensor. Refer to Quick
Connect Fittings in this section.
FUEL SYSTEM PRESSURE RELEASE
PROCEDUREÐEXCEPT 2.2L/2.5L TBI AND 3.0L
WARNING: RELEASE FUEL SYSTEM PRESSURE
BEFORE SERVICING FUEL SYSTEM COMPONENTS.
WHEN SERVICING FLEXIBLE FUEL VEHICLES,
WEAR METHANOL RESISTANT GLOVES AND EYE
PROTECTION AND AVOID BREATHING FUMES. DO
NOT ALLOW METHANOL/GASOLINE MIXTURES TO
CONTACT SKIN. SERVICE VEHICLES IN WELL VEN-
TILATED AREAS AND AVOID IGNITION SOURCES.
NEVER SMOKE WHILE SERVICING THE VEHICLE.
(1) Disconnect negative cable from battery.
(2) Remove fuel filler cap.
(3) Remove the protective cap from the fuel pres-
sure test port on the fuel rail (Fig. 2). (4) Place the open end of fuel pressure release
hose, tool number C-4799-1, into an approved gaso-
line container or a container approved for gasoline/
methanol mixtures. Connect the other end of hose
C-4799-1 to the fuel pressure test port (Fig. 3). Fuel
pressure will bleed off through the hose into the gas-
oline container. Fuel gauge C-4799-A contains hose
C-4799-1.
FUEL SYSTEM PRESSURE RELEASE
PROCEDUREÐ2.2L/2.5L TBI
CAUTION: Before servicing the fuel pump, fuel
lines, fuel filter, throttle body, or fuel injector, re-
lease fuel system pressure.Fig. 1 Methanol Concentration Sensor
14 - 4 FUEL SYSTEMS Ä
Page 1745 of 2438

(1) Loosen fuel filler cap to release fuel tank pres-
sure. (2) Disconnect injector wiring harness connector at
edge of throttle body (Fig. 4). (3) Connect a jumper wire between terminal Num-
ber 1 of the injector harness and engine ground. (4) Connect a jumper wire to the positive terminal
Number 2 of the injector harness and touch the bat-
tery positive post for no longer than 5 seconds .
This releases system pressure. (5) Remove jumper wires.
(6) Continue fuel system service.
FUEL SYSTEM PRESSURE RELEASE
PROCEDUREÐ3.0L
(1) Disconnect the fuel rail electrical harness from
the engine harness. Refer to Group 8W, Wiring Dia-
grams. (2) Connect one end of a jumper wire to the A142
circuit terminal of the fuel rail harness connector. (3) Connect the other end of the jumper wire to a
12 volt power source. (4) Connect one end of a jumper wire to a good
ground source. (5) Momentarily ground one of the injectors by
connecting the other end of the jumper wire to an in-
jector terminal in the harness connector. Repeat pro-
cedure for 2 to 3 injectors.
FUEL PUMP ASSEMBLY
The fuel pump assembly consists of the fuel pump
and the reservoir body. The reservoir body takes the place of an internal
fuel tank reservoir. The reservoir maintains fuel at
the pump inlet during all driving conditions, espe-
cially when the fuel level is low. The system uses a positive displacement, gerotor
gear, immersible pump with a permanent magnet
electric motor (Fig. 5). The pump draws fuel through
a strainer and pushes it through the electric motor to
the outlet. The pump contains three check valves.
One valve relieves internal fuel pump pressure and
regulates maximum pump output. Another valve, in-
side the pump assembly in the fuel return circuit,
prevents fuel tank leakage if the line is damaged
during an accident. The third valve, in the pump out-
let, maintains pump pressure during engine off con-
ditions. The fuel pump relay provides voltage to the
fuel pump. All pumps have a maximum stall pres-
sure output of approximately 930 kPa (135 psi). All front wheel drive car fuel systems, except
Turbo III and flexible fuel AA-body vehicles use the
same fuel pump. Turbo III and flexible fuel AA-Body
vehicles each use different fuel pumps although they
look similar to pumps used in other vehicles. Release fuel system pressure before servicing the
fuel tank, fuel pump, fuel lines, fuel filter, or parts of
the fuel rail. Follow the Fuel System Pressure Re-
lease procedure to relieve fuel system pressure.
Fig. 2 Fuel Pressure Test PortÐTypical
Fig. 3 Releasing Fuel PressureÐEngines With Test Ports On Fuel Rail
Fig. 4 Injector Harness ConnectorÐ2.2L/2.5L TBI
Ä FUEL SYSTEMS 14 - 5