fuel filter DODGE NEON 2000 Service User Guide

carbon monoxide emissions. The type and amount of
oxygenate used in the blend is important.
The following are generally used in gasoline
blends:
Ethanol- (Ethyl or Grain Alcohol) properly
blended, is used as a mixture of 10 percent ethanol
and 90 percent gasoline. Gasoline blended with etha-
nol may be used in your vehicle.
MTBE/ETBE- Gasoline and MTBE (Methyl Ter-
tiary Butyl Ether) blends are a mixture of unleaded
gasoline and up to 15 percent MTBE. Gasoline and
ETBE (Ethyl Tertiary Butyl Ether) are blends of gas-
oline and up to 17 percent ETBE. Gasoline blended
with MTBE or ETBE may be used in your vehicle.
Methanol- Methanol (Methyl or Wood Alcohol) is
used in a variety of concentrations blended with
unleaded gasoline. You may encounter fuels contain-
ing 3 percent or more methanol along with other
alcohols called cosolvents.
DO NOT USE GASOLINE CONTAINING
METHANOL.
Use of methanol/gasoline blends may result in
starting and driveability problems and damage criti-
cal fuel system components.
Problems that are the result of using methanol/
gasoline blends are not the responsibility of
DaimlerChrysler Corporation and may not be covered
by the vehicle warranty.
Reformulated Gasoline
Many areas of the country are requiring the use of
cleaner-burning fuel referred to asReformulated
Gasoline. Reformulated gasoline are specially
blended to reduce vehicle emissions and improve air
quality.
DaimlerChrysler Corporation strongly supports the
use of reformulated gasoline whenever available.
Although your vehicle was designed to provide opti-
mum performance and lowest emissions operating on
high quality unleaded gasoline, it will perform
equally well and produce even lower emissions when
operating on reformulated gasoline.
Materials Added to Fuel
Indiscriminate use of fuel system cleaning agents
should be avoided. Many of these materials intended
for gum and varnish removal may contain active sol-
vents of similar ingredients that can be harmful to
fuel system gasket and diaphragm materials.
FUEL DELIVERY SYSTEM
OPERATION
The fuel delivery system consists of: the electric
fuel pump, fuel filter/fuel pressure regulator, fuel
tubes/lines/hoses, fuel rail, fuel injectors, fuel tank,
accelerator pedal and throttle cable.A fuel return system is used on all models (all
engines). Fuel is returned through the fuel pump
module and back into the fuel tank through the fuel
filter/fuel pressure regulator. A separate fuel return
line from the engine to the tank is no longer used
with any engine.
The fuel tank assembly consists of: the fuel tank,
filler tube, fuel gauge sending unit/electric fuel pump
module, a rollover valve(s) and a pressure-vacuum
filler cap.
Also to be considered part of the fuel system is the
evaporation control system or Onboard Refueling
Vapor recovery (ORVR). This is designed to reduce
the emission of fuel vapors into the atmosphere. The
description and function of the Evaporative Control
System is found in the Emission Control Systems
section.
FUEL PUMP MODULE
DESCRIPTION
The fuel pump module is installed in the fuel tank
(Fig. 1).
OPERATION
The fuel pump module contains the following:
²Electric fuel pump
²Fuel pump reservoir
²Inlet strainer
²Fuel filter/pressure regulator
²Fuel gauge sending unit
²Fuel supply line connection
Fig. 1 Fuel Pump Module
1 ± FUEL FILTER/PRESSURE REGULATOR
2 ± FUEL LEVEL SENSOR
3 ± FUEL RESERVOIR
4 ± INLET STRAINER
5 ± FLOAT
PLFUEL SYSTEM 14 - 3
DESCRIPTION AND OPERATION (Continued)

The inlet strainer, fuel pressure regulator and fuel
level sensor are the only serviceable items. If the fuel
pump requires service, replace the fuel pump module.
ELECTRIC FUEL PUMP
DESCRIPTION
The electric fuel pump is located in and is part of
the fuel pump module. It is a positive displacement,
gerotor type, immersible pump with a permanent
magnet electric motor. The fuel pump module is sus-
pended in fuel in the fuel tank.
OPERATION
The pump draws fuel through a strainer and
pushes it through the motor to the outlet. The pump
contains a check valve. The valve, in the pump out-
let, maintains pump pressure during engine off con-
ditions. The fuel pump relay provides voltage to the
fuel pump. The fuel pump has a maximum dead-
headed pressure output of approximately 880 kPa
(130 psi). The regulator adjusts fuel system pressure
to approximately 338 kPa (49 psi).
FUEL GAUGE SENDING UNIT
DESCRIPTION
The fuel gauge sending unit (fuel level sensor) is
attached to the side of the fuel pump module. The
sending unit consists of a float, an arm, and a vari-
able resistor (track). The resistor track is used to
send electrical signals to the instrument cluster for
fuel gauge operation and are then transmitted to the
engine controller for OBDII emission requirements.
OPERATION
For fuel gauge operation:As fuel level
increases, the float and arm move up. This increases
the sending unit resistance, causing the fuel gauge to
read full. As fuel level decreases, the float and arm
move down. This decreases the sending unit resis-
tance causing the fuel gauge to read empty.
After this fuel level signal is sent to the instru-
ment cluster, the instrument cluster will transmit
the data across the J1850 bus circuit to the PCM.
For OBD II emission requirements:The voltage
signal is sent to the instrument cluster to indicate
fuel level. The cluster transmits the fuel level to the
PCM where it is used to prevent a false setting of
misfire and fuel system monitor trouble codes. This
occurs if the fuel level in the tank is less than
approximately 15 percent of its rated capacity.
FUEL FILTER/FUEL PRESSURE REGULATOR
DESCRIPTION
A combination fuel filter and fuel pressure regula-
tor is used on all gas powered engines. It is located
on the top of the fuel pump module. A separate frame
mounted fuel filter is not used.
OPERATION
Fuel Pressure Regulator Operation:The pres-
sure regulator is a mechanical device that is cali-
brated to maintain fuel system operating pressure of
approximately 338 kPa (49 psi) at the fuel injectors.
It contains a diaphragm, calibrated springs and a
fuel return valve. The internal fuel filter (Fig. 2) is
also part of the assembly.
Fuel is supplied to the filter/regulator by the elec-
tric fuel pump through an opening tube at the bot-
tom of filter/regulator.
The fuel pump module contains a check valve to
maintain some fuel pressure when the engine is not
operating. This will help to start the engine.
If fuel pressure at the pressure regulator exceeds
approximately 49 psi, an internal diaphragm closes
and excess fuel pressure is routed back into the tank
through the pressure regulator. A separate fuel
return line is not used with any gas powered engine.
FUEL TANK
OPERATION
All models pass a full 360 degree rollover test
without fuel leakage. To accomplish this, fuel and
vapor flow controls are required for all fuel tank con-
nections.
All models are equipped with either one or two
rollover valves mounted into the top of the fuel tank
(or pump module).
An evaporation control system is connected to the
rollover valve(s) to reduce emissions of fuel vapors
into the atmosphere. When fuel evaporates from the
fuel tank, vapors pass through vent hoses or tubes to
a charcoal canister where they are temporarily held.
When the engine is running, the vapors are drawn
into the intake manifold. Certain models are also
equipped with a self-diagnosing system using a Leak
Detection Pump (LDP). Refer to the Emission Control
System for additional information.
FUEL RAIL
DESCRIPTION
The fuel rail supplies the necessary fuel to each
individual fuel injector and is mounted to the intake
manifold (Fig. 3).
14 - 4 FUEL SYSTEMPL
DESCRIPTION AND OPERATION (Continued)

OPERATION
The fuel pressure regulator is no longer mounted
to the fuel rail on any engine. It is now located on
the fuel tank mounted fuel pump module. Refer toFuel Filter/Fuel Pressure Regulator in the Fuel
Delivery System section of this group for information.
The fuel rail is not repairable.
FUEL INJECTORS
DESCRIPTION
The injectors are positioned in the intake manifold
with the nozzle ends directly above the intake valve
port (Fig. 4).
OPERATION
The fuel injectors are 12 ohm electrical solenoids
(Fig. 5). The injector contains a pintle that closes off
an orifice at the nozzle end. When electric current is
supplied to the injector, the armature and needle
move a short distance against a spring, allowing fuel
to flow out the orifice. Because the fuel is under high
pressure, a fine spray is developed in the shape of a
hollow cone. The spraying action atomizes the fuel,
adding it to the air entering the combustion chamber.
Fuel injectors are not interchangeable between
engines.
PRESSURE-VACUUM FILLER CAP
OPERATION
The loss of any fuel or vapor out of the filler neck
is prevented by the use of a safety filler cap. The cap
will release pressure only under significant pressure
of 10.9 to 13.45 kPa (1.58 to 1.95 psi). The vacuum
release for all gas caps is between 1.94 and 2.94 kPa
(0.28 and 0.43 psi). The cap must be replaced by a
similar unit if replacement is necessary.
Fig. 2 Side ViewÐFilter/Regulator
1 ± INTERNAL FUEL FILTER
2 ± FUEL FLOW TO FUEL INJECTORS
3 ± FUEL FILTER/FUEL PRESSURE REGULATOR
4 ± O-RINGS
5 ± EXCESS FUEL BACK TO TANK
6 ± FUEL INLET
7 ± CALIBRATED SPRINGS
8 ± RUBBER GROMMET AT PUMP MODULE
9 ± LOCKING TAB
Fig. 3 Fuel Rail
Fig. 4 Fuel Injector LocationÐTypical
1 ± FUEL RAIL
2 ± INTAKE MANIFOLD
3 ± FUEL INJECTORS
PLFUEL SYSTEM 14 - 5
DESCRIPTION AND OPERATION (Continued)

REMOVAL AND INSTALLATION
AUTOMATIC SHUTDOWN RELAY
The relay is located in the Power Distribution Cen-
ter (PDC) (Fig. 12). The PDC is located next to the
battery in the engine compartment. For the location
of the relay within the PDC, refer to the PDC cover
for location. Check electrical terminals for corrosion
and repair as necessary.
FUEL PUMP RELAY
The fuel pump relay is located in the PDC. The
inside top of the PDC cover has a label showing relay
and fuse location.
FUEL PUMP MODULE
REMOVAL
WARNING: RELEASE FUEL SYSTEM PRESSURE
BEFORE SERVICING FUEL SYSTEM COMPONENTS.
SERVICE VEHICLES IN WELL VENTILATED AREAS
AND AVOID IGNITION SOURCES. NEVER SMOKE
WHILE SERVICING THE VEHICLE.
(1) Drain the fuel. Refer to Draining Fuel Tank in
the Fuel Tank section of this group.
WARNING: THE FUEL RESERVOIR OF THE FUEL
PUMP MODULE DOES NOT EMPTY OUT WHEN THE
TANK IS DRAINED. THE FUEL IN THE RESERVOIR
WILL SPILL OUT WHEN THE MODULE IS
REMOVED.
(2) Remove fuel tank, refer to the Fuel Tank
removal/installation section.
(3) Lower tank.(4) Use Special Tool 6856 to remove fuel pump
module locknut (Fig. 15).
(5) Remove fuel pump and O-ring seal from tank.
Discard old seal.
INSTALLATION
(1) Wipe seal area of tank clean and place a new
seal in position in the tank opening.
(2) Position fuel pump in the tank. Make sure the
alignment tab on the underside of the fuel pump
module flange sits in the notch on the fuel tank (Fig.
14).
(3) Position the locknut over the fuel pump mod-
ule.
Fig. 12 Power Distribution Center (PDC)
Fig. 13 Fuel Pump Module Removal
1 ± FUEL FILTER/PRESSURE REGULATOR
2 ± FUEL LINE
3 ± LOCKNUT
Fig. 14 Alignment Tab
14 - 12 FUEL SYSTEMPL

(4) Tighten the locknut using Special Tool 6856 to
55 N´m (40.5 ft. lbs.) (Fig. 15).
CAUTION: Over tightening the pump lock ring may
result in a leak.
(5) Install fuel tank, refer to the Fuel Tank remov-
al/installation section.
(6) Lower vehicle.
(7) Fill fuel tank. Check for leaks.
FUEL FILTER / PRESSURE REGULATOR
REMOVAL
WARNING: THE FUEL SYSTEM IS UNDER A CON-
STANT PRESSURE, EVEN WITH ENGINE OFF.
BEFORE SERVICING THE FUEL FILTER/FUEL
PRESSURE REGULATOR, THE FUEL SYSTEM
PRESSURE MUST BE RELEASED.
(1) Refer to Fuel System Pressure Release in the
Fuel Delivery System section of this group.
The fuel filter/fuel pressure regulator is located on
the top of fuel pump module. Fuel pump module
removal is not necessary.
(2) Raise vehicle on hoist.
(3) Disconnect fuel supply line at the Filter/Regu-
lator nipple (refer to Quick Connect Fittings in this
section).
(4) Depress locking spring tab on side of Fuel/Reg-
ulator (Fig. 16) and rotate 90É counter-clockwise and
pull out.
NOTE: Make sure that the upper and lower O-rings
are on the Filter/Regulator assembly.
INSTALLATION
Lightly lubricate the O-rings with engine oil.
(1) Insert Filter/Regulator into the opening in the
fuel pump module, align the two hold down tabs with
the flange.
(2) While applying downward pressure, rotate the
Filter/Regulator clockwise until the the spring tab
engages the locating slot (Fig. 17).
(3) Connect the fuel line to the Filter/Regulator.
(4) Lower vehicle from hoist.
Fig. 15 Fuel Tank Locknut
1 ± SPECIAL TOOL 6856
2 ± LOCKNUT
Fig. 16 Locking Spring Tab
1 ± FUEL FILTER/PRESSURE REGULATOR
2 ± SPRING TAB
3 ± LOCATING SLOT
Fig. 17 Spring Tab In Locating Slot
1 ± FUEL FILTER/PRESSURE REGULATOR
2 ± SPRING TAB
3 ± LOCATING SLOT
PLFUEL SYSTEM 14 - 13
REMOVAL AND INSTALLATION (Continued)

(7) Disconnect fuel pump module electrical connec-
tor and ground wire (Fig. 31).
(8) Disconnect the fuel tube from Fuel Filter/Reg-
ulator. Refer to Quick Connect Fittings in the Fuel
Delivery section of this group.
(9) Disconnect fuel filler tube and filler vent tube
from filler hose at fuel tank.
(10) Support tank with transmission jack. Loosen
tank mounting straps and lower tank slightly.
(11) Remove tank mounting straps and lower tank.
INSTALLATION
(1) Position fuel tank on transmission jack.
(2) Raise tank into position.
(3) Tighten fuel tank strap nuts to 22.5 N´m (200
in. lbs.) torque. Remove transmission jack. Ensure
straps are not twisted or bent.(4) Connect fuel filler tube tank inlet nipple.
Tighten clamp.
(5) Connect EVAP vent hose.
(6) Attach fuel tubes to pump module and chassis
fuel tube. Refer to Quick Connect Fittings in the Fuel
Delivery section of this Group.
(7) Attach electrical connector and ground wire to
fuel pump module.
(8) Install vapor lines to EVAP canister.
(9) Install EVAP canister.
(10) Lower vehicle.
(11) Fill fuel tank, install filler cap, and connect
battery cable.
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
until the ignition switch is turned to the Off posi-
tion.
(12) Use the DRB scan tool ASD Fuel System Test
to pressurize the fuel system. Check for leaks.
FUEL FILLER NECK
REMOVAL
(1) Loosen fuel filler tube cap.
(2) Remove fuel filler neck screws (Fig. 32).
(3) Raise and support vehicle.
(4) Remove splash shield from wheel well.
(5) Disconnect fuel fill vapor tube.
(6) Disconnect fuel filler tube from fuel tank.
(7) Remove groundstrap from body.
(8) Remove filler neck (Fig. 33).
Fig. 29 EVAP Canister
Fig. 30 Fuel Tank
Fig. 31 Pump Module Electrical Connector
1 ± ELECTRICAL CONNECTOR
2 ± FUEL LINE
PLFUEL SYSTEM 14 - 17
REMOVAL AND INSTALLATION (Continued)

Pending ConditionsÐ
²Misfire DTC
²Front Oxygen Sensor Response
²Front Oxygen Sensor Heater Monitor
²Front Oxygen Sensor Electrical
²Rear Oxygen Sensor Rationality (middle check)
²Rear Oxygen Sensor Heater Monitor
²Rear Oxygen Sensor Electrical
²Fuel System Monitor
²All TPS faults
²All MAP faults
²All ECT sensor faults
²Purge flow solenoid functionality
²Purge flow solenoid electrical
²All PCM self test faults
²All CMP and CKP sensor faults
²All injector and ignition electrical faults
²Idle Air Control (IAC) motor functionality
²Vehicle Speed Sensor
²Brake switch
²Intake air temperature
ConflictÐThe catalyst monitor does not run if
any of the following are conditions are present:
²EGR Monitor in progress
²Fuel system rich intrusive test in progress
²EVAP Monitor in progress
²Time since start is less than 60 seconds
²Low fuel level
²Low ambient air temperature
SuspendÐThe Task Manager does not mature a
catalyst fault if any of the following are present:
²Oxygen Sensor Monitor, Priority 1
²Upstream Oxygen Sensor Heater, Priority 1
²EGR Monitor, Priority 1
²EVAP Monitor, Priority 1
²Fuel System Monitor, Priority 2
²Misfire Monitor, Priority 2
NON-MONITORED CIRCUITS
OPERATION
The PCM does not monitor all circuits, systems
and conditions that could have malfunctions causing
driveability problems. However, problems with these
systems may cause the PCM to store diagnostic trou-
ble codes for other systems or components. For exam-
ple, a fuel pressure problem will not register a fault
directly, but could cause a rich/lean condition or mis-
fire. This could cause the PCM to store an oxygen
sensor or misfire diagnostic trouble code.
The major non-monitored circuits are listed below
along with examples of failures modes that do not
directly cause the PCM to set a DTC, but for a sys-
tem that is monitored.FUEL PRESSURE
The fuel pressure regulator controls fuel system
pressure. 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 the
PCM to store an oxygen sensor or fuel system diag-
nostic trouble code.
SECONDARY IGNITION CIRCUIT
The PCM cannot detect an inoperative ignition coil,
fouled or worn spark plugs, ignition cross firing, or
open spark plug cables.
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. It may set a EGR or Fuel
system fault or O2S.
FUEL INJECTOR MECHANICAL MALFUNCTIONS
The PCM cannot determine if a fuel injector is
clogged, the needle is sticking or if the wrong injector
is installed. However, these could result in a rich or
lean condition causing the PCM to store a diagnostic
trouble code for either misfire, an oxygen sensor, or
the fuel system.
EXCESSIVE OIL CONSUMPTION
Although the PCM monitors engine exhaust oxygen
content 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 element.
VACUUM ASSIST
The PCM cannot detect leaks or restrictions in the
vacuum circuits of vacuum assisted engine control
system devices. However, these could cause the PCM
to store a MAP sensor diagnostic trouble code and
cause a high idle condition.
PCM SYSTEM GROUND
The PCM cannot determine a poor system ground.
However, one or more diagnostic trouble codes may
be generated as a result of this condition. The mod-
ule should be mounted to the body at all times, also
during diagnostic.
PLEMISSION CONTROL SYSTEMS 25 - 23
DESCRIPTION AND OPERATION (Continued)