1999 DODGE NEON Service Repair Manual

The exhaust ball joint consists of two bolts, two
springs, and a ball joint seal ring, which is a sepa-
rate part from the exhaust pipe.
EXHAUST FLEX-JOINT COUPLING (LEV)
An exhaust flex-joint coupling is used on Low
Emission Vehicles (LEV) (Fig. 3). This coupling is
used to secure the catalytic converter to the exhaust
manifold. This coupling actually moves back and
forth as the engine moves, preventing breakage that
could occur from the back and forth motion of a
transverse mounted engine.
The exhaust flex-joint is welded to the catalytic
converter.
CATALYTIC CONVERTER
There is no regularly scheduled maintenance on
any Chrysler catalytic converter (Fig. 4). If damaged,
the converter must be replaced.
CAUTION: Due to exterior physical similarities of
some catalytic converters with pipe assemblies,
extreme care should be taken with replacement
parts.
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
catalytic converter. Failure of the catalytic converter
can occur due to temperature increases caused by
unburned fuel passing through the converter.
The use of the catalysts also involves some non-au-
tomotive problems. Unleaded gasoline must be used
to avoid poisoning the catalyst core. Do not allow
engine to operate above 1200 RPM in neutral for
extended periods over 5 minutes. This condition may
result in excessive exhaust system/floor pan temper-
atures because of no air movement under the vehicle.
Fig. 2 Ball Joint Connection
Fig. 3 Flex-Joint (LEV)
Fig. 4 Exhaust System ComponentsÐTypical
11 - 2 EXHAUST SYSTEM AND INTAKE MANIFOLDPL
GENERAL INFORMATION (Continued)

HEAT SHIELDS
The heat shield (Fig. 5) is needed to protect both
the car and the environment from the high tempera-
tures developed in the vicinity of the catalytic con-
verter.
CAUTION: Avoid application of rust prevention
compounds or undercoating materials to exhaust
system floor pan heat shield on cars if equipped.
Light over-spray near the edges is permitted. Appli-
cation of coating will greatly reduce the efficiency
of the heat shields resulting in excessive floor pan
temperatures and objectionable fumes.
EXHAUST GAS RECIRCULATION (EGR) SYSTEM
To assist in the control of oxides of nitrogen (NOx)
in engine exhaust, some engines are equipped with
an exhaust gas recirculation system. The use of
exhaust gas to dilute incoming air/fuel mixtures low-
ers peak flame temperatures during combustion, thus
limiting the formation of NOx.
Exhaust gases are taken from the number four
exhaust port through a hole in the end of the cylin-
der head. REFER TO GROUP 25, EMISSION SYS-
TEMS FOR A COMPLETE DESCRIPTION,
DIAGNOSIS AND SERVICE PROCEDURES ON
THE EXHAUST GAS RECIRCULATION SYSTEM
AND COMPONENTS.
DESCRIPTION AND OPERATION
INTAKE MANIFOLD SOHC
The intake manifold is a molded plastic composi-
tion, attached to the cylinder head with ten fasten-
ers. This long branch design enhances low and
midrange torque. If removing the intake manifold for
any reason, the fasteners can not be reused.
INTAKE MANIFOLD DOHC
The intake manifold is a two piece aluminum cast-
ing, attached to the cylinder head with ten fasteners.
This long branch fan design enhances low and
midrange torque.
EXHAUST MANIFOLD
The exhaust manifold is made of nodular cast iron
for strength and high temperatures. Exhaust gasses
exit through a machined, articulated joint connection
to the exhaust pipe.
Fig. 5 Heat Shield Installation
PLEXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 3
GENERAL INFORMATION (Continued)

DIAGNOSIS AND TESTING
REMOVAL AND INSTALLATION
EXHAUST PIPE AND MUFFLER
REMOVAL
(1) Raise vehicle on hoist and apply penetrating oil
to band clamp fastener of component being removed
(Fig. 6).NOTE: Do not use petroleum-based lubricants
when removing/installing muffler or exhaust pipe
isolators as it may compromise the life of the part.
A suitable substitute is a mixture of liquid dish
soap and water.
(2) Loosen band clamp and remove support insula-
tors at muffler (Fig. 7). Remove muffler from exhaust
pipe.
EXHAUST SYSTEM DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
EXCESSIVE EXHAUST NOISE
(UNDER HOOD)1. Exhaust manifold cracked or
broken.1. Replace manifold.
2. Manifold to cylinder head leak. 2. Tighten manifold and/or replace
gasket.
3. EGR Valve Leakage. 3. See Below:
(a) EGR valve to manifold gasket. (a) Tighten bolts and/or replace
gasket.
(b) EGR valve to EGR tube gasket. (b) Tighten bolts and/or replace
gasket.
(c) EGR tube to intake manifold
gasket.(c) Tighten bolts and/or replace
gasket.
4. Exhaust flex joint. (non LEV) 4. See Below:
(a) Spring height, not correctly
installed.(a) Check spring height, both sides
(specification is 32.5 mm, 1.28 inch)
look for source of spring height
variation if out of specification
(b) Exhaust sealing ring defective. (b) Inspect seal for damage on
round spherical surface. If no
damage is evident, check for
exhaust restriction causing high back
pressure on heavy acceleration.
5. Exhaust Flex joint to manifold
leak (LEV).5.Tighten nuts or replace gasket.
6. Exhaust flex joint (LEV). 6. Replace catalytic converter
assembly.
7. Pipe and shell noise from front
exhaust pipe.7. Characteristic of single wall pipes.
EXCESSIVE EXHAUST NOISE 1. Leaks at pipe joints. 1. Tighten or replace clamps at
leaking joints.
2. Burned, blown, or rusted out
exhaust pipe or muffler.2. Replace muffler or exhaust pipes.
3. Restriction in muffler or tailpipe. 3. Remove restriction, if possible or
replace as necessary.
4. Catalytic converter material in
muffler.4. replace muffler and converter
assembly. Check fuel injection and
ignition systems for proper operation.
11 - 4 EXHAUST SYSTEM AND INTAKE MANIFOLDPL

(3) Disconnect downstream heated oxygen sensor
from the catalytic converter pipe.
(4) Remove clamp at the catalytic converter to
exhaust pipe slip joint (Fig. 8). Separate at slip joint.
(5) When removing exhaust pipe, raise rear of
vehicle to relieve body weight from rear suspension
to provide clearance between pipe and lateral arms.
(6) Remove catalytic converter to exhaust manifold
attaching fasteners (Fig. 9).
(7) Remove catalytic converter from vehicle.
Remove and discard flange gasket (LEV only).
(8) Clean ends of pipes and/or muffler to assure
mating of all parts. Discard broken or worn insula-
tors, rusted clamps, supports and attaching parts.
Fig. 6 Slip Joint ConnectionÐTypical
Fig. 7 Exhaust Pipe and Muffler Support
InsulatorsÐTypical
Fig. 8 Catalytic Converter to Exhaust Pipe
Connection
Fig. 9 Catalytic Converter to Exhaust Manifold
ConnectionÐFederal
Fig. 10 Catalytic Converter to Exhaust Manifold
ConnectionÐLEV
PLEXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 5
REMOVAL AND INSTALLATION (Continued)

NOTE: When replacement is required on any com-
ponent of the exhaust system, you must use origi-
nal equipment parts (or their equivalent).
INSTALLATION
When assembling exhaust systemdo nottighten
clamps until components are aligned and clearances
are checked.
(1) Assemble catalytic convertor to exhaust mani-
fold connection. Use a new flange gasket (LEV only)
(Fig. 9) or (Fig. 10).
(2) Assemble exhaust pipe to catalytic convertor
and the support to the underbody
(3) Install the muffler to exhaust pipe and the sup-
ports to the underbody.
(4) Working from the front of system;
(5) Align and tighten the catalytic convertor to
exhaust manifold ball joint bolts to 27 N´m (20 ft.
lbs.) (Fig. 9) or flex-joint attaching nuts (LEV) to 28
N´m (250 in. lbs.).
(6) Align each component to maintain position and
proper clearance with underbody parts (Fig. 11) and
tighten band clamps to specifications (Fig. 12).
CAUTION: Band (Torca) clamps should never be
tighten such that the two sides of the clamps are
bottomed out against the center hourglass shaped
center block. Once this occurs, the clamp has lost
its clamping force and must be replaced.
(7) Connect the downstream heated oxygen sensor
and lower the vehicle.
INTAKE MANIFOLDÐSOHC ENGINE
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) Disconnect negative cable from battery.
(2) Remove fuel filler cap.
(3) Remove the fresh air inlet duct from air
cleaner (Fig. 15).
(4) Remove the protective cap from the fuel pres-
sure test port on the fuel rail (Fig. 13).
(5) Place the open end of fuel pressure release
hose, Special Tool C-4799-1, into an approved gaso-
line container. Connect the other end of hose to the
fuel pressure test port (Fig. 14). Fuel pressure will
bleed off through the hose into the gasoline con-
tainer. Fuel gauge C-4799-A contains hose C-4799-1.
(6) Perform fuel system pressure release procedure
before attempting any repairs.
(7) Disconnect the fuel supply line quick connect at
the fuel tube assembly.
Fig. 11 Exhaust Clearance
Fig. 12 Band Clamp (Torca)
Fig. 13 Fuel Pressure Test Port
11 - 6 EXHAUST SYSTEM AND INTAKE MANIFOLDPL
REMOVAL AND INSTALLATION (Continued)

WARNING: WRAP SHOP TOWELS AROUND HOSE
TO CATCH ANY GASOLINE SPILLAGE.
(8) Remove fuel rail assembly attaching screws
and remove fuel rail assembly from engine. Cover
injector holes with suitable covering.
CAUTION: Do not set fuel injectors on their tips,
damage may occur to the injectors
(9) Remove clean air duct and upper air filter
housing (Fig. 15).
(10) Remove accelerator, kickdown and speed con-
trol cables from throttle lever and bracket. Refer to
Group 14, Fuel System Throttle Body Removal for
procedures.
(11) Disconnect Idle Air Control (IAC) motor and
Throttle Position Sensor (TPS) wiring connectors
(Fig. 16).
(12) Disconnect vacuum hoses from throttle body
(Fig. 16).(13) Disconnect Manifold Absolute Pressure/Intake
Air Temperature Sensor (TMAP), electrical connector
(Fig. 17). Disconnect vapor and brake booster hoses.
(14) Disconnect knock sensor electrical connector
(Fig. 18) and disconnect wiring harness from tab
located on the intake manifold.
(15) Disconnect wiring at starter.
(16) Remove transmission to throttle body support
bracket fasteners at the throttle body and loosen the
fasteners at the transmission end.
(17) Remove throttle body.
(18) Remove EGR tube bolts at the valve and at
the intake manifold (Fig. 19). Remove tube from
engine.
(19) Remove the intake manifold to inlet water
tube support fastener (Fig. 20).
(20) Remove 10 intake manifold screws and wash-
ers. Discard the fasteners. Remove intake manifold.
Fig. 14 Releasing Fuel Pressure
Fig. 15 Clean Air Duct to Throttle Body Assembly
Fig. 16 Idle Air Control (IAC) Motor and Throttle
Position Sensor (TPS) Wiring Connectors and
Vacuum Hose Connection
Fig. 17 Intake Manifold Electrical and Vacuum Hose
Connections
PLEXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 7
REMOVAL AND INSTALLATION (Continued)

INSTALLATION
Before installing manifold. Clean all mating sur-
faces. Replace all seals, with new seals. All intakemanifold fasteners and washers are to be discarded
andNEWfasteners and washers are to be used.
(1) Install intake manifold onto cylinder head and
tighten fasteners to 12 N´m (105 in. lbs.) in sequence
shown in (Fig. 20).
(2) Install intake manifold to water inlet support.
Tighten fastener (Fig. 20) to 12 N´m (105 in. lbs.).
(3) Remove covering from fuel injector holes and
insure the holes are clean. Install fuel rail assembly
to intake manifold. Tighten screws to 23 N´m (200 in.
lbs.).
(4) Connect PCV and brake booster hoses.
(5) Inspect quick connect fittings for damage,
replace if necessary Refer to Group 14, Fuel System
for procedure. Apply a light amount of clean engine
oil to fuel inlet tube. Connect fuel supply hose to fuel
rail assembly. Check connection by pulling on connec-
tor to insure it locked into position.
(6) Install throttle body. Tighten fastener to 22
N´m (200 in. lbs.). Install transmission to throttle
body support bracket and tighten to 11.9 N´m (105
in. lbs.) at the throttle body first. Next tighten the
bracket at the transmission.
(7) Connect Manifold Absolute Pressure/Intake Air
Temperature Sensor (TMAP) wiring connector.
(8) Connect knock sensor connector, and wiring at
starter. Connect wiring harness to intake manifold
tab.
(9) Connect Idle Air Control (IAC) motor and
Throttle Position Sensor (TPS) wiring connectors.
(10) Connect vacuum hoses to throttle body.
(11) Install accelerator, kickdown and speed con-
trol cables to their bracket and connect them to the
throttle lever. Refer to Group 14, Fuel System Throt-
tle Body Installation for procedure.
(12) Loose assemble the EGR tube onto valve and
intake manifold finger tight. Tighten tube fasteners
at the EGR valve first to 11 N´m (95 in. lbs.) then,
tighten the intake manifold side fasteners to 11 N´m
(95 in. lbs.).
(13) Install clean air duct to air filter housing.
Tighten clamp to 3 N´m (30 in. lbs.).
(14) Connect negative cable to battery.
(15) Install fresh air duct to air cleaner and
tighten wing nut.
(16) With the DRB scan tool use ASD Fuel System
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
selected.
Fig. 18 Knock Sensor
Fig. 19 EGR Tube Assembly
Fig. 20 Intake Manifold Tightening Sequence
11 - 8 EXHAUST SYSTEM AND INTAKE MANIFOLDPL
REMOVAL AND INSTALLATION (Continued)

INTAKE MANIFOLDÐDOHC ENGINE
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) Disconnect negative cable from battery.
(2) Remove fuel filler cap.
(3) Loosen wing nut on intake and remove fresh
air inlet duct (Fig. 23).
(4) Remove the protective cap from the fuel pres-
sure test port on the fuel rail (Fig. 21).
(5) Place the open end of fuel pressure release
hose, Special Tool C-4799-1, into an approved gaso-
line container. Connect the other end of hose to the
fuel pressure test port (Fig. 22). Fuel pressure will
bleed off through the hose into the gasoline con-
tainer. Fuel gauge C-4799-A contains hose C-4799-1.
(6) Disconnect the fuel supply line quick-connect at
the fuel tube assembly.
(7) Remove clean air inlet duct.WARNING: WRAP SHOP TOWELS AROUND HOSE
TO CATCH ANY GASOLINE SPILLAGE.
(8) Disconnect the coolant temperature sensor
(Fig. 24).
(9) Disconnect heater hose from intake manifold.
(10) Disconnect heater tube from bottom of intake
manifold.
(11) Disconnect upper radiator hose and coolant
recovery hose.
(12) Remove fuel rail assembly attaching screws
and remove fuel rail assembly from engine. Cover
injector holes with suitable covering.
CAUTION: Do not set fuel injectors on their tips,
damage may occur to the injectors
Fig. 21 Fuel Pressure Test PortÐTypical
Fig. 22 Releasing Fuel PressureÐTypical
Fig. 23 Fresh Air Inlet Duct
Fig. 24 Engine Coolant Temperature Sensor
PLEXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 9
REMOVAL AND INSTALLATION (Continued)