fuel filter CHEVROLET DYNASTY 1993 Owner's Manual

FUEL SYSTEM PRESSURE
Fuel system pressure is regulated at the fuel rail
or throttle body by a fuel pressure regulator. Refer to
the Fuel System Pressure Chart for pressure specifi-
cations. The chart reflects system pressure when the
pump is energized with the engine not running and
without vacuum applied to the pressure regulator.
FUEL PUMP PRESSURE TESTÐALL EXCEPT
2.2L/2.5L TBI AND 3.0L MPI
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.
The specifications in the Fuel Pressure chart re-
flect system pressure with the vacuum hose removed
from the pressure regulator. (1) Remove the vacuum hose from the pressure
regulator before checking fuel pressure. (2) Release fuel system pressure. Refer to the Fuel
System Pressure Release procedure in this section. (3) Connect Fuel Pressure Gauge C-4799 to service
port on fuel rail (Fig. 6).
CAUTION: When using the ASD Fuel System Test,
the Auto Shutdown (ASD) Relay remains energized
for either 7 minutes, until the test is stopped, or un-
til the ignition switch is turned to the Off position.
(4) Place the ignition key in the ON position. Us-
ing the DRBII scan tool, access ASD Fuel System
Test. The ASD Fuel System Test will activate the
fuel pump and pressurize the system. If the gauge reads the specification listed in the
Fuel System Pressure chart, further testing is not re-
quired. If pressure is not correct, record the pressure
and remove gauge. Use the DRBII scan tool ASD
Fuel System Test to pressurize the system. Ensure
fuel does not leak from the fuel rail service valve. In-
stall protective cover on fuel rail service valve. If pressure is below specifications, proceed to Fuel
System Pressure Below Specifications . If pres-
sure is above specifications, proceed to Fuel System
Pressure Above Specifications .
Fuel System Pressure Below Specifications
If the fuel pressure reading in step (4) was below
specifications, test the system according to the fol-
lowing procedure.
WARNING: RELEASE FUEL SYSTEM PRESSURE
BEFORE DISCONNECTING A FUEL SYSTEM HOSE
OR COMPONENT.
(a) Perform Fuel Pressure Release procedure.
(b) Install Fuel Pressure Gauge C-4799 and Fuel
Pressure Test Adapter 6539 in the fuel supply line
between the fuel tank and fuel filter at the rear of
vehicle (Fig. 7). (c) Using the DRBII scan tool, with the ignition
key in the ON position, repeat the ASD Fuel Sys-
tem Test.
Fig. 5 Fuel PumpÐTypical
FUEL SYSTEM PRESSURE
Fig. 6 Fuel Pressure TestingÐEngines With Service Ports
14 - 6 FUEL SYSTEMS Ä

² If pressure is at least 5 psi higher than reading
recorded in step (4), replace fuel filter. ² If no change is observed, gently squeeze the re-
turn hose. If fuel pressure increases, replace pressure
regulator. If gauge reading does not change while
squeezing the return hose, the problem is either a
plugged inlet strainer or defective fuel pump. Fuel System Pressure Above Specifications
If the fuel pressure reading in step (4) was above
specifications, test the system according to the fol-
lowing procedure.
WARNING: RELEASE FUEL SYSTEM PRESSURE
BEFORE DISCONNECTING A FUEL SYSTEM HOSE
OR COMPONENT.
(a) Perform Fuel Pressure Release procedure.
(b) Remove the fuel return line hose from the
fuel pump at fuel tank. (c) Connect Fuel Pressure Test Adapter 6541 to
the return line (Fig. 8). Place the other end of
adapter 6541 into an approved gasoline container
or a container approved for methanol/gasoline mix-
tures (minimum 2 gallon size). All return fuel will
flow into container. (d) Using the DRBII scan tool, with the ignition
key in the ON position, repeat the ASD Fuel Sys-
tem Test.
² If pressure is now correct, replace fuel pump as-
sembly. ² If pressure is still above specifications, remove
fuel return hose from chassis fuel tubes (at engine).
Attach Fuel Pressure Test Connect Adapter 6541 to
the fuel return hose and place other end of hose in
clean container (Fig. 9). Repeat test. If pressure is
now correct, check for restricted fuel return line. If
no change is observed, replace fuel pressure regula-
tor.
FUEL PUMP PRESSURE TESTÐ2.2L/2.5L TBI and
3.0L MPI ENGINES
WARNING: RELEASE FUEL SYSTEM PRESSURE
BEFORE DISCONNECTING A FUEL SYSTEM HOSE
OR COMPONENT.
The specifications in the Fuel Pressure chart re-
flect system pressure with the vacuum hose removed
from the pressure regulator. Remove the vacuum line
from the pressure regulator on 3.0L engines before
testing fuel system pressure. The pressure regulators
on 2.2L/2.5L TBI engines are not vacuum assisted. (1) Perform fuel system pressure release.
(2) Remove fuel supply hose quick connector from
the chassis lines (at the engine). (3) Connect Fuel Pressure Gauge C-4799 to Fuel
Pressure Test Adapter 6539 (Fig. 10). Install the
adapter between fuel supply hose and chassis fuel
line assembly.
Fig. 7 Fuel Pressure TestFig. 8 Fuel Pressure Return Test
Fig. 9 Fuel Return Connection
Ä FUEL SYSTEMS 14 - 7

CAUTION: When using the ASD Fuel System Test,
the Auto Shutdown (ASD) Relay remains energized
for either 7 minutes, until the test is stopped, or un-
til the ignition switch is turned to the Off position.
(4) Place the ignition key in the ON position. Us-
ing the DRBII scan tool, access ASD Fuel System
Test. The ASD Fuel System Test will activate the
fuel pump and pressurize the system. If the gauge reads the pressure shown in the Fuel
System Pressure chart, further testing is not re-
quired. If pressure is not correct, record the pressure
and remove gauge. If pressure is below specifications, proceed to Fuel
System Pressure Below Specifications . If pressure
is above specifications, proceed to Fuel System
Pressure Above Specifications .
Fuel System Pressure Below Specifications
If the fuel pressure reading in step (4) was below
specifications, test the system according to the fol-
lowing procedure.
WARNING: RELEASE FUEL SYSTEM PRESSURE
BEFORE DISCONNECTING A FUEL SYSTEM HOSE
OR COMPONENT.
(a) Perform Fuel Pressure Release procedure.
(b) Install Fuel Pressure Gauge C-4799 and Fuel
Pressure Adapter 6433 in the fuel supply line (Fig.
7) between the fuel tank and fuel filter. (c) Using the DRBII scan tool, with the ignition
key in the ON position, repeat the ASD Fuel Sys-
tem Test.
² If pressure is at least 5 psi higher than reading
recorded in step (4), replace fuel filter. ² If no change is observed, gently the squeeze re-
turn hose. If fuel pressure increases, replace pressure
regulator. If the gauge reading does not change while
squeezing the return hose, the problem is either a
plugged inlet strainer or defective fuel pump. Fuel System Pressure Above Specifications If the fuel pressure reading in step (4) was above
specifications test the system according to the follow-
ing procedure.
WARNING: FUEL SYSTEM PRESSURE MUST BE
RELEASED BEFORE A FUEL SYSTEM HOSE OR
COMPONENT IS DISCONNECTED.
(a) Perform Fuel Pressure Release procedure.
(b) Install Fuel Pressure Gauge C-4799 and Fuel
Pressure Adapter 6433 in the fuel supply line be-
tween the fuel tank and fuel filter (Fig. 7). (c) Remove the fuel return line hose from the
fuel pump at fuel tank. Connect Fuel Pressure Test
Adapter 6541 to the return line (Fig. 8). Place the
other end of adapter 6541 into an approved gaso-
line container or a container approved for gasoline/
methanol mixtures (minimum 2 gallon size). All
return fuel will flow into container. (d) Using the DRBII scan tool, with the ignition
key in the ON position, repeat the ASD Fuel Sys-
tem Test.
² If pressure is now correct, replace fuel pump as-
sembly. ²
If pressure is still above specifications, remove fuel
return hose from chassis fuel tubes (at engine). Attach
Fuel Pressure Test Connect Adapter 6541 to the fuel re-
turn hose and place other end of hose in clean approved
gasoline container or a container approved for metha-
nol/gasoline mixtures (Fig. 9). Repeat test. If pressure is
now correct, check for restricted fuel return line. If no
change is observed, replace fuel pressure regulator.
MECHANICAL MALFUNCTIONS
Mechanical malfunctions are more difficult to diag-
nose with this system. The powertrain control mod-
ule (PCM) compensates for some mechanical
malfunctions. If engine performance problems are en-
countered, and no fault codes are displayed, the prob-
lem may be mechanical rather than electronic.
FUEL PUMP MODULE 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.
Remove the fuel tank to service the fuel pump. Re-
fer to Fuel Tank Section for fuel tank removal. (1) Using a hammer and a brass drift punch care-
fully tap lock ring counter clockwise to release pump
(Fig. 11).
Fig. 10 Fuel Pressure Gauge and Adapter
14 - 8 FUEL SYSTEMS Ä

(2) Remove fuel pump and O-ring seal from tank.
Discard old seal.
FUEL PUMP MODULE INSTALLATION
WARNING: FUEL PUMP MODULES DESIGNED FOR
GASOLINE ONLY VEHICLES CANNOT BE USED ON
FLEXIBLE FUEL AA-BODY VEHICLES. WHEN SER-
VICING THE FUEL SYSTEM OF A FLEXIBLE FUEL
VEHICLE, ONLY USE ORIGINAL EQUIPMENT OR
EQUIVALENT REPLACEMENT COMPONENTS.
(1) Wipe seal area of tank clean and place a new
O-ring seal in position on pump. (2) Position fuel pump in tank with locking ring.
(3) Using a hammer and brass drift, drive ring
around in clockwise direction to lock pump in place.
CAUTION: Over tightening the pump lock ring
may result in a leak.
(4) Install tank. Refer to the Fuel Tank Section in
this Group.
FUEL PUMP STRAINER SERVICE
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.
REMOVAL
(1) Remove fuel pump module. Refer to Fuel Pump
Module in this section. (2) Bend locking tabs on fuel pump reservoir as-
sembly to clear locking tangs on the fuel pump
strainer (Fig. 12). (3) Pull strainer off.
(4) Remove strainer O-ring from the fuel pump
reservoir body. (5) Remove any contaminants by washing the in-
side of the fuel tank.
INSTALLATION
WARNING: FUEL STRAINERS (AND O-RINGS) DE-
SIGNED FOR GASOLINE ONLY VEHICLES CANNOT
BE USED ON FLEXIBLE FUEL AA-BODY VEHICLES.
WHEN SERVICING THE FUEL SYSTEM OF A FLEX-
IBLE FUEL VEHICLE, ONLY USE ORIGINAL EQUIP-
MENT OR EQUIVALENT REPLACEMENT
COMPONENTS.
(1) Lubricate the strainer O-ring with Mopar Sili-
cone Spray Lube. (2) Insert strainer O-ring into outlet of strainer so
that it sits evenly on the step inside the outlet. (3) Push strainer onto the inlet of the fuel pump
reservoir body. Make sure the locking tabs on the
reservoir body lock over the locking tangs on the
strainer. (4) Install fuel pump module. Refer to Fuel Pump
Module in this section.
FUEL FILTERÐALL VEHICLES
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.
Fig. 11 Fuel Pump Service
Fig. 12 Fuel Strainer Service
Ä FUEL SYSTEMS 14 - 9

REMOVAL
(1) Perform the Fuel System Pressure Release pro-
cedure. (2) ) Remove the fuel filter retaining screw (Fig.
13). Remove fuel filter from mounting plate.
(3) Wrap a shop towel around hoses to absorb fuel.
Remove quick-connect fittings at filter and fuel supply
tube. Refer to Quick-Connect Fittings in this section.
INSTALLATION
WARNING: FUEL FILTERS DESIGNED FOR GASO-
LINE ONLY VEHICLES CANNOT BE USED ON
FLEXIBLE FUEL AA-BODY VEHICLES. WHEN SER-
VICING THE FUEL SYSTEM OF A FLEXIBLE FUEL
VEHICLE, ONLY USE ORIGINAL EQUIPMENT OR
EQUIVALENT REPLACEMENT COMPONENTS.
(1) Connect quick-connect fuel fittings to the filter
and fuel supply line. Refer to Quick-Connect Fittings
in this section. (2) Position filter assembly on mounting plate and
tighten mounting screw to 8 N Im (75 in. lbs.) torque.
CAUTION: When using the ASD Fuel System Test,
the Auto Shutdown (ASD) Relay remains energized
for either 7 minutes, until the test is stopped, or un-
til the ignition switch is turned to the Off position.
(3) Place the ignition key in the ON position. Us-
ing the DRBII scan tool, access ASD Fuel System
Test. The ASD Fuel System Test will activate the
fuel pump and pressurize the system. Inspect for
leaks.
FUEL HOSES, CLAMPS, AND QUICK CONNECT
FITTINGS
HOSES AND CLAMPS
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.
WARNING: FUEL SYSTEM HOSES AND TUBES DE-
SIGNED FOR GASOLINE ONLY VEHICLES CANNOT
BE USED ON FLEXIBLE FUEL VEHICLES. WHEN
SERVICING THE FUEL SYSTEM OF A FLEXIBLE
FUEL VEHICLE, ONLY USE ORIGINAL EQUIPMENT
OR EQUIVALENT REPLACEMENT COMPONENTS.
Inspect all hose connections (clamps and quick con-
nect fittings) for completeness and make sure they
are not leaking. Hoses that are cracked, scuffed,
swelled, rub against other vehicle components or
show any sign of wear, should be replaced.
When installing hoses, route them away from compo-
nents they could rub against. Avoid contact with clamps
or other components that cause abrasions or scuffing.
Ensure rubber hoses are properly routed and avoid heat
sources. The clamps have rolled edge to prevent the clamp
from cutting into the hose. Only use clamps that are
original equipment or equivalent. Other types of clamps
may cut into the hoses and cause high pressure fuel
leaks. Tighten hose clamps to 1 N Im (10 in. lbs.) torque.
QUICK CONNECT FITTINGS
Most fuel lines have quick connect fittings. The fit-
tings speed up the installation and removal of fuel
lines (Fig. 14). Quick connect fittings consist of a metal casing, a
black plastic release ring, a metal locking retainer,
and internal O-rings.
METAL QUICK CONNECT FITTINGS
The fuel filter and fuel rail use steel quick-connect
fittings. The fitting contains non-serviceable sealed
O-rings. The fittings contain a plastic disconnect tool.
The quick-connect fitting consists of the O-rings, cas-
ing, disconnect tool and a retainer (Fig. 14). When the
Fig. 13 Fuel Filter
Fig. 14 Metal Quick-Connect Fittings
14 - 10 FUEL SYSTEMS Ä

Fig. 16 Fuel Tank, Filter, and Chassis Line RoutingÐExcept Flexible Fuel AA-Body
14 - 12 FUEL SYSTEMS Ä

Fig. 17 Fuel Tank, Filter, and Chassis Line RoutingÐFlexible Fuel AA-Body
Ä FUEL SYSTEMS 14 - 13

WARNING: FUEL FILLER TUBE CAPS DESIGNED
FOR GASOLINE ONLY VEHICLES CANNOT BE
USED ON FLEXIBLE FUEL AA-BODY VEHICLES.
WHEN SERVICING THE FUEL SYSTEM OF A FLEX-
IBLE FUEL VEHICLE, ONLY USE ORIGINAL EQUIP-
MENT OR EQUIVALENT REPLACEMENT
COMPONENTS.
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. 1).
(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 methanol/
gasoline mixtures. Connect the other end of hose
C-4799-1 to the fuel pressure test port (Fig. 2). 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.
(1) Loosen fuel filler cap to release fuel tank pres-
sure. (2) Disconnect injector wiring harness connector at
edge of throttle body (Fig. 3). (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-
FUEL TANK CAPACITIES
Fig. 1 Fuel Pressure Test PortÐTypical
Fig. 2 Releasing Fuel PressureÐEngines With Test Ports On Fuel Rail
Ä FUEL SYSTEMS 14 - 15

once the system has entered closed loop. Refer to
Modes of Operation in this section for an explanation
of closed loop operation.
NON-MONITORED CIRCUITS
The PCM does not monitor the following circuits,
systems and conditions that could have malfunctions
that result in driveability problems. Diagnostic trou-
ble codes may not be displayed for these conditions.
However, problems with these systems may cause di-
agnostic trouble codes to be displayed for other sys-
tems. For example, a fuel pressure problem will not
register a fault directly, but could cause a rich or
lean condition. This could cause an oxygen sensor
fault to be stored in the PCM. Fuel Pressure - Fuel pressure is controlled by the
fuel pressure regulator. The PCM cannot detect a
clogged fuel pump inlet filter, clogged in-line fuel fil-
ter, or a pinched fuel supply or return line. However,
these could result in a rich or lean condition causing
an oxygen sensor fault. Secondary Ignition Circuit - The PCM cannot
detect an inoperative ignition coil, fouled or worn
spark plugs, ignition cross firing, or open spark plug
cables. Engine Timing - The PCM cannot detect an incor-
rectly indexed timing chain, camshaft sprocket and
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 fault 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
determine if the fuel injector is clogged, the pintle is
sticking or the wrong injector is installed. However,
these could result in a rich or lean condition causing
an oxygen sensor fault to be stored in the PCM. Excessive Oil Consumption - Although the PCM
monitors the exhaust stream oxygen content through
the oxygen sensor when the system is in closed loop,
it cannot determine excessive oil consumption. Throttle Body Air Flow - The PCM cannot detect
a clogged or restricted air cleaner inlet or filter ele-
ment. Evaporative System - The PCM will not detect a
restricted, plugged or loaded evaporative purge can-
ister. Vacuum Assist - Leaks or restrictions in the vac-
uum circuits of vacuum assisted engine control sys-
tem devices are not monitored by the PCM. However,
these could result in a MAP sensor fault being stored
in the PCM. PCM System Ground - The PCM cannot deter-
mine a poor system ground. However, a diagnostic
trouble code may be generated as a result of this con-
dition. PCM Connector Engagement - The PCM cannot
determine spread or damaged connector pins. How-
ever, a diagnostic trouble code may be generated as a
result of this condition.
HIGH AND LOW LIMITS
The powertrain control module (PCM) compares in-
put signal voltages from each input device with es-
tablished high and low limits that are programmed
into it for that device. If the input voltage is not
within specifications and other diagnostic trouble
code criteria are met, a diagnostic trouble code will
be stored in memory. Other diagnostic trouble code
criteria might include engine RPM limits or input
voltages from other sensors or switches that must be
present before a fault condition can be verified.
DIAGNOSTIC TROUBLE CODE DESCRIPTION
When a diagnostic trouble code appears, it indi-
cates the powertrain control module (PCM) has rec-
ognized an abnormal condition in the system.
Diagnostic trouble codes can be obtained from the
malfunction indicator lamp (instrument panel Check
Engine lamp) on the Instrument Panel or from the
DRBII scan tool. Diagnostic trouble codes indicate
the results of a failure but do not identify the failed
component directly.
Fig. 3 Data Link Connector LocationÐAG and AJ Vehicles
14 - 42 FUEL SYSTEMS Ä

2.2L/2.5L SINGLE POINT FUEL INJECTIONÐSERVICE PROCEDURES INDEX
page page
Canister Purge Solenoid ................... 53
Electric Exhaust Gas Recirculation Transducer (EET) Service ............................... 53
Fuel Fitting ............................. 50
Fuel Injector ............................ 51
Fuel Lines and Hoses ..................... 48
Fuel Pressure Regulator ................... 51 Fuel System Pressure Release Procedure
...... 48
Heated Oxygen Sensor (O
2Sensor) .......... 54
Idle Air Control Motor ..................... 53
Manifold Absolute Pressure Sensor ........... 53
PCM Service ............................ 54
Throttle Body ............................ 48
Throttle Position Sensor ................... 52
FUEL LINES AND HOSES
Perform the Fuel System Pressure Relief Procedure
before servicing the fuel system. The procedure must
be done to bleed fuel pressure from the system before
removing clamps or hoses. Use care when removing fuel hoses to prevent dam-
age to hose or hose nipple. Always use new hose
clamps, of the correct type, during reassembly. Tighten
hose clamps to 1 N Im (10 in. lbs.) torque. Do not use
aviation style clamps on this system or hose
damage may result.
FUEL SYSTEM PRESSURE RELEASE PROCEDURE
CAUTION: Before servicing the fuel pump, fuel lines,
fuel filter, throttle body, or fuel injector, release fuel
system pressure.
(1) Loosen fuel filler cap to release fuel tank pres-
sure. (2) Disconnect injector wiring harness connector at
edge of throttle body (Fig. 1). (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 battery
positive post for no longer than 5 seconds . This
releases system pressure. (5) Remove jumper wires.
(6) Continue fuel system service.
THROTTLE BODY
CAUTION: The fuel system is under a constant pres-
sure of 270 kPa (39 psi). When servicing the fuel
portion of the throttle body, release fuel pressure
before disconnecting any tubes. Refer to the fuel
pressure release procedure.
Always reassemble throttle body components with
new O-rings and seals where applicable. Never use
silicone lubricants on O-rings or seals, damage may
result. Use care when removing fuel tubes to prevent
damage to quick connect fittings or tube ends. Refer to Fuel Hoses, Clamps, and Quick Connect Fittings
in the Fuel Delivery Section of this Group.
REMOVAL
(1) Remove air cleaner (Fig. 2).
(2) Perform fuel system pressure release procedure.
(3) Disconnect negative battery cable.
(4) Disconnect vacuum hoses and electrical connec-
tors (Fig. 3).
Fig. 1 Injector Harness Connector
Fig. 2 Throttle Body and Air Cleaner Assembly
14 - 48 FUEL SYSTEMS Ä