2000 DODGE NEON fuel cap release

exhaust manifold, the other is a unique under-floor
catalytic converter (Fig. 3).
The three-way catalytic converter simultaneously
converts three exhaust emissions into harmless
gases. Specifically, HC and CO emissions are con-
verted into water (H2O) and carbon dioxide (CO2).
Oxides of Nitrogen (NOx) are converted into elemen-
tal Nitrogen (N) and water. The three-way catalyst is
most efficient in converting HC, CO and NOx at the
stoichiometric air fuel ratio of 14.7:1.
The oxygen content in a catalyst is important for
efficient conversion of exhaust gases. When a high
oxygen content (lean) air/fuel ratio is present for an
extended period, oxygen content in a catalyst can
reach a maximum. When a rich air/fuel ratio is
present for an extended period, the oxygen content in
the catalyst can become totally depleted. When this
occurs, the catalyst fails to convert the gases. This is
known as catalyst ªpunch through.9
Catalyst operation is dependent on its ability to
store and release the oxygen needed to complete the
emissions-reducing chemical reactions. As a catalyst
deteriorates, its ability to store oxygen is reduced.
Since the catalyst's ability to store oxygen is some-
what related to proper operation, oxygen storage can
be used as an indicator of catalyst performance.
Refer to the appropriate Powertrain Diagnostic Pro-
cedure for diagnosis of a catalyst related Diagnostic
Trouble Code (DTC).
The combustion reaction caused by the catalyst
releases additional heat in the exhaust system, caus-ing temperature increases in the area of the reactor
under severe operating conditions. Such conditions
can exist when the engine misfires or otherwise does
not operate at peak efficiency.Do notremove spark
plug wires from plugs or by any other means short
out cylinders, if exhaust system is equipped with a
Fig. 2 Flex-Joint
1 ± BELLOWS
2 ± PROTECTIVE ENDCAPS
3 ± FLANGE
Fig. 3 Catalytic Converters
1 ± CATALYTIC CONVERTER (LEV EMISSION)
2 ± CLOSE-COUPLED CATALYTIC CONVERTER (ULEV
EMISSION)
3 ± UNDER-FLOOR CATALYTIC CONVERTER (ULEV EMISSION)
4 ± OXYGEN SENSORS5 ± OXYGEN SENSOR
6 ± CATALYTIC CONVERTER (FEDERAL EMISSION)
7 ± OXYGEN SENSOR
11 - 2 EXHAUST SYSTEMPL
DESCRIPTION AND OPERATION (Continued)

FUEL SYSTEM
TABLE OF CONTENTS
page page
FUEL DELIVERY SYSTEM.................... 1FUEL INJECTION SYSTEM.................. 21
FUEL DELIVERY SYSTEM
TABLE OF CONTENTS
page page
DESCRIPTION AND OPERATION
FUEL REQUIREMENTS.....................1
GASOLINE/OXYGENATE BLENDS.............2
FUEL DELIVERY SYSTEM...................3
FUEL PUMP MODULE......................3
ELECTRIC FUEL PUMP.....................4
FUEL GAUGE SENDING UNIT................4
FUEL FILTER/FUEL PRESSURE REGULATOR....4
FUEL TANK..............................4
FUEL RAIL...............................4
FUEL INJECTORS.........................5
PRESSURE-VACUUM FILLER CAP............5
ONBOARD REFUELING VAPOR RECOVERY....6
CONTROL VALVE/PRESSURE RELIEF.........6
QUICK-CONNECT FITTINGS.................6
ROLLOVER VALVES.......................7
FUEL TUBES/LINES/HOSES AND CLAMPS......8
SERVICE PROCEDURES
FUEL SYSTEM PRESSURE RELEASE
PROCEDURE...........................8INJECTOR CONNECTOR....................8
DRAINING FUEL TANK.....................9
HOSES AND CLAMPS......................9
QUICK-CONNECT FITTINGS.................9
REMOVAL AND INSTALLATION
AUTOMATIC SHUTDOWN RELAY............12
FUEL PUMP RELAY.......................12
FUEL PUMP MODULE.....................12
FUEL FILTER / PRESSURE REGULATOR......13
FUEL PUMP INLET STRAINER..............14
FUEL LEVEL SENSOR.....................14
FUEL INJECTORS........................15
FUEL TANK.............................16
FUEL FILLER NECK.......................17
ACCELERATOR PEDAL....................18
THROTTLE CABLE.......................19
SPECIFICATIONS
TORQUE...............................20
DESCRIPTION AND OPERATION
FUEL REQUIREMENTS
OPERATION
Your engine is designed to meet all emissions reg-
ulations and provide excellent fuel economy and per-
formance when using high quality unleaded gasoline
having an octane rating of 87. The use of premium
gasoline is not recommended. The use of premium
gasoline will provide no benefit over high quality reg-
ular gasoline, and in some circumstances may result
in poorer performance.
Light spark knock at low engine speeds is not
harmful to your engine. However, continued heavyspark knock at high speeds can cause damage and
immediate service is required. Engine damage result-
ing from operation with a heavy spark knock may
not be covered by the new vehicle warranty.
Poor quality gasoline can cause problems such as
hard starting, stalling and hesitations. If you experi-
ence these symptoms, try another brand of gasoline
before considering service for the vehicle.
The American Automobile Manufacturers Associa-
tion, AAMA, has issued gasoline specifications to
define the minimum fuel properties necessary to
deliver enhanced performance and durability for your
vehicle. DaimlerChrysler Corporation recommends
the use of gasoline that meet the AAMA specifica-
tions if they are available.
PLFUEL SYSTEM 14 - 1

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)

INSTALLATION
(1) Connect electrical connectors at all fuel injec-
tors. To install connector, refer to (Fig. 8). Push con-
nector onto injector (1) and then push and lock red
colored slider (2). Verify connector is locked to injec-
tor by lightly tugging on connector.
DRAINING FUEL TANK
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) Remove fuel filler cap.
(2) Perform the Fuel System Pressure Release pro-
cedure.
(3) Disconnect negative cable from battery.
(4) Raise vehicle and support.
(5) Remove quick connect cap from drain port.
(6) Drain fuel tank into holding tank or a properly
labeledGasolinesafety container.
(7) Replace quick connect cap.
HOSES AND CLAMPS
Inspect all hose connections (clamps and quick con-
nect fittings) for completeness and leaks. Replace
cracked, scuffed, or swelled hoses. Replace hoses that
rub against other vehicle components or show sign of
wear.
Fuel injected vehicles use specially constructed
hoses. When replacing hoses, only use hoses marked
EFM/EFI.
When installing hoses, ensure that they are routed
away from contact with other vehicle components
that could rub against them and cause failure. Avoid
contact with clamps or other components that cause
abrasions or scuffing. Ensure that rubber hoses are
properly routed and avoid heat sources.
The hose clamps have rolled edges 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´m (10 in. lbs.) torque.
QUICK-CONNECT FITTINGS
REMOVAL
When disconnecting a quick-connect fitting, the
retainer will remain on the fuel tube nipple.
WARNING: RELEASE FUEL SYSTEM PRESSURE
BEFORE DISCONNECTING A QUICK-CONNECT FIT-
TINGS. REFER TO THE FUEL PRESSURE RELEASE
PROCEDURE.
(1) Disconnect negative cable from battery or aux-
iliary jumper terminal.
(2) Perform Fuel Pressure Release Procedure.
Refer to the Fuel Pressure Release Procedure in this
section.
Fig. 7 Fuel Injectors
Fig. 8 Remove/Install Injector Connector
PLFUEL SYSTEM 14 - 9
SERVICE PROCEDURES (Continued)

(3) Install retaining clip.
(4) Apply a light coating of clean engine oil to the
O-ring on the nozzle end of each injector.
(5) Insert fuel injector nozzles into openings in
intake manifold. Seat the injectors in place. Tighten
fuel rail mounting screws to 22.5 N´m63 N´m
(200630 in. lbs.).
(6) Attach electrical connectors to fuel injectors,
refer to the fuel injector connector section for electri-
cal connector installation.
(7) Connect fuel supply tube to fuel rail. Refer to
Quick Connect Fittings in the Fuel Delivery Section
of this Group.
FUEL TANK
REMOVAL
(1) Disconnect the negative battery cable (Fig. 28).
(2) Perform fuel system pressure release, refer to
the fuel system pressure release procedure in this
section.
(3) Raise and support vehicle on hoist.
(4) Disconnect vapor line from EVAP canister tube.
(5) Remove EVAP canister (Fig. 29).
(6) Drain fuel tank. Remove the drain port cap and
remove fuel. Drain fuel tank into holding tank or a
properly labeledGasolinesafety container. Reinstall
drain port cap when done draining fuel (Fig. 30).
Fig. 25 Fuel Rail and Injectors
1 ± FUEL SUPPLY LINE
2 ± FUEL LINE QUICK-CONNECTS
3 ± IGNITION COIL
4 ± FUEL RAIL
5 ± FUEL INJECTOR
Fig. 26 Fuel Injector Retainer
1 ± RETAINER
2 ± FUEL RAIL
3 ± FUEL INJECTOR
Fig. 27 Fuel Injector O-Rings
1 ± FUEL INJECTOR
2 ± NOZZLE
3 ± TOP (FUEL ENTRY)
Fig. 28 Battery Cable
14 - 16 FUEL SYSTEMPL
REMOVAL AND INSTALLATION (Continued)