
INSTALLATION
INSTALLATION - REAR HEATER LINES
(1) Install line into underbody straps.
(2) Install line into front hose and install hose
clamp.
(3) Connect quick fitting at rear of line.
(4) Lower vehicle.
(5) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
INSTALLATION - REAR AIR CONDITIONING
LINES
(1) Before installation, replace all O-rings and gas-
kets. Coat all sealing surfaces with approved wax-
free refrigerant oil.
(2) Install A/C line into rear block with nylon
wedge.
(3) Install A/C lines into five underbody brackets.
(4) Connect forward compression fittings.
(5) Install bolt at sealing block to rear A/C hous-
ing.
(6) Install ABS harness into clips.
(7) Install heater hoses into underbody brackets.
(8) Install lines into front hoses and install hose
clamps.
(9) Lower vehicle.
(10) Evacuate and recharge system.
(11) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
Fig. 13 UNDERBODY LINE WEDGES
1 - O-RING
2 - DISCHARGE LINE
3 - NYLON WEDGE
4 - SEALING BLOCK
5 - VISE
6 - SUCTION LINE
24 - 108 PLUMBING - REARRS
UNDERBODY LINES (Continued)
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DIAGNOSIS AND TESTING - DIESEL
SUPPLEMENTAL HEATER - DCHA
The following table lists possible fault symptoms of
diesel fueled heaters.
SYMPTOM POSSIBLE CAUSES
Smell of diesel fuel Check heater system integration in vehicle's fuel system. Check fuel
lines for leakage, kinks or obstructions. If OK, Inspect the inlet muffler,
drain as necessary. Re-test the unit and re-inspect. Inspect the
exhaust tube and heater unit for the presence of external fuel. If a
volume is observed on the unit or in the exhaust tube or after draining
and testing. Remove heater unit from vehicle and repair or replace
components as required.
Heater does not achieve full load
operation.Check heater operation with DRB-III and replace components as
required.
Continuous white smoke from heater
exhaust during combustion operation.Check heater operation with DRB-III and replace components as
required. White smoke is typical in extreme weather conditions.
Heater can not be switched off. Check heater operation with DRB-III and replace components as
required.
Heater does not operate. Diagnosis cabin heater ECU using the DRB-III and the procedures
listed in Vehicle Performance under Cabin Heater Diagnosis in Group
18.
Loss of coolant (Leakage) or heater
develops smoke during combustion
operation and exhaust has an
extremely sweet smell.Inspect coolant hoses for leakage, kinks or loose hose connection.
Inspect the exhaust tube assembly for continuous flow, if OK there is
an internal heater leak and unit should be inspected and components
should be replaced as required.
Loss of fuel (dripping). Check heater system integration in vehicles fuel system. Check fuel
line connection for leakage. If OK there is an internal leak and unit
should be inspected and replaced as required.
EXHAUST TUBE
REMOVAL
WARNING: THERE IS A POTENTIAL DANGER OF
SKIN BURNS AS THE HEATER AND ITS COMPO-
NENTS MAY BE VERY HOT. MAKE SURE THE
HEATER IS ALLOWED TO COOL DOWN BEFORE
ANY SERVICE WORK IS ATTEMPTED.
WARNING: THERE IS A POTENTIAL DANGER OF
SKIN BURNS AS THE EXHAUST SYSTEM MAY BE
VERY HOT. MAKE SURE THE EXHAUST SYSTEM IS
ALLOWED TO COOL DOWN BEFORE ANY SERVICE
WORK IS ATTEMPTED ON THE CABIN HEATER.
(1) Elevate vehicle on a lift taking note of the
exhaust tube flexible section.
(2) Remove the exhaust clamp at the flexible pipe
and steel pipe connection (Fig. 1).
(3) Remove the clamp at the flexible pipe connec-
tion and the heater unit housing (if required).(4) Remove the three screws holding the exhaust
pipe to the body.
(5) Remove the steel exhaust pipe from the vehi-
cle.
(6) Remove the flexible exhaust pipe from the
vehicle (if required).
INSTALLATION
(1) Install the flexible exhaust pipe to the heater
unit. Tighten mounting clamp.
(2) Position the steel exhaust pipe to the flexible
exhaust and install and tighten the mounting clamp.
(3) Install the three exhaust pipe screws, adjust
pipe placement as needed and tighten the screws.
(4) Install the clamp to connect the steel exhaust
pipe to the flexible exhaust pipe and tighten clamp.
(5) Check exhaust pipe exhaust end placement and
make any final adjustments.
(6) Lower vehicle from lift.
24 - 110 DIESEL SUPPLEMENTAL HEATER - DCHA - BUXRS
DIESEL SUPPLEMENTAL HEATER - DCHA - BUX (Continued)
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EMISSIONS CONTROL
TABLE OF CONTENTS
page page
EMISSIONS CONTROL
DESCRIPTION
DESCRIPTION - VEHICLE EMISSION
CONTROL INFORMATION LABEL..........1
DESCRIPTION - TRIP DEFINITION.........1
DESCRIPTION - MONITORED COMPONENT . 1
OPERATION - NON-MONITORED CIRCUITS . . 5
DESCRIPTION - MONITORED SYSTEMS....6DESCRIPTION - HIGH AND LOW LIMITS....9
OPERATION
OPERATION - SYSTEM..................9
DRB IIITSTATE DISPLAY TEST MODE.....10
EVAPORATIVE EMISSIONS................11
EXHAUST GAS RECIRCULATION...........20
ON-BOARD DIAGNOSTICS................24
EMISSIONS CONTROL
DESCRIPTION
DESCRIPTION - VEHICLE EMISSION CONTROL
INFORMATION LABEL
All models have a Vehicle Emission Control Infor-
mation (VECI) Label. Chrysler permanently attaches
the label in the engine compartment. It cannot be
removed without defacing information and destroying
the label.
The label contains the vehicle's emission specifica-
tions and vacuum hose routings. All hoses must be
connected and routed according to the label.
DESCRIPTION - TRIP DEFINITION
A ªTripº means vehicle operation (following an
engine-off period) of duration and driving mode such
that all components and systems are monitored at
least once by the diagnostic system. The monitors
must successfully pass before the PCM can verify
that a previously malfunctioning component is meet-
ing the normal operating conditions of that compo-
nent. For misfire or fuel system malfunction, the
MIL may be extinguished if the fault does not recur
when monitored during three subsequent sequential
driving cycles in which conditions are similar to
those under which the malfunction was first deter-
mined.
Anytime the MIL is illuminated, a DTC is stored.
The DTC can self erase only after the MIL has been
extinguished. Once the MIL is extinguished, the
PCM must pass the diagnostic test for the most
recent DTC for 40 warm-up cycles (80 warm-up
cycles for the Fuel System Monitor and the Misfire
Monitor). A warm-up cycle can best be described by
the following:
²The engine must be running²A rise of 40ÉF in engine temperature must occur
from the time when the engine was started
²
Engine coolant temperature must crossover 160ÉF
²A ªdriving cycleº that consists of engine start up
and engine shut off.
Once the above conditions occur, the PCM is con-
sidered to have passed a warm-up cycle. Due to the
conditions required to extinguish the MIL and erase
the DTC, it is most important that after a repair has
been made, all DTC's be erased and the repair veri-
fied by running 1±good trip.
DESCRIPTION - MONITORED COMPONENT
There are several components that will affect vehi-
cle emissions if they malfunction. If one of these com-
ponents malfunctions the Malfunction Indicator
Lamp (Check Engine) will illuminate.
Some of the component monitors are checking for
proper operation of the part. Electrically operated
components now have input (rationality) and output
(functionality) checks. Previously, a component like
the Throttle Position sensor (TPS) was checked by
the PCM for an open or shorted circuit. If one of
these conditions occurred, a DTC was set. Now there
is a check to ensure that the component is working.
This is done by watching for a TPS indication of a
greater or lesser throttle opening than MAP and
engine rpm indicate. In the case of the TPS, if engine
vacuum is low and engine rpm is 1600 or greater and
the TPS indicates a small throttle opening, a DTC
will be set. The same applies to low vacuum and
1600 rpm.
Any component that has an associated limp in will
set a fault after 1 trip with the malfunction present.
Refer to the Diagnostic Trouble Codes Description
Charts (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/POWERTRAIN CONTROL
MODULE - DESCRIPTION) and the appropriate
Powertrain Diagnostic Procedure Manual for diag-
nostic procedures.
RSEMISSIONS CONTROL25-1
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EVAPORATIVE EMISSIONS
TABLE OF CONTENTS
page page
EVAPORATIVE EMISSIONS
OPERATION - EVAPORATION CONTROL
SYSTEM............................11
SPECIFICATIONS
TORQUE............................12
EVAP/PURGE SOLENOID
DESCRIPTION.........................13
OPERATION...........................13
REMOVAL.............................13
INSTALLATION.........................13
FUEL FILLER CAP
DESCRIPTION.........................13
OPERATION...........................13
LEAK DETECTION PUMP
REMOVAL.............................14
INSTALLATION.........................14
ORVR
OPERATION...........................14DIAGNOSIS AND TESTING - VEHICLE DOES
NOT FILL............................16
P C V VA LV E
DESCRIPTION.........................17
OPERATION...........................17
DIAGNOSIS AND TESTING - PCV SYSTEM . . . 17
VAPOR CANISTER
DESCRIPTION.........................18
OPERATION...........................18
REMOVAL
REMOVAL...........................19
REMOVAL - REAR EVAP CANISTER.......19
INSTALLATION
INSTALLATION.......................19
INSTALLATION - REAR EVAP CANISTER . . . 19
EVAPORATIVE EMISSIONS
OPERATION - EVAPORATION CONTROL
SYSTEM
The evaporation control system prevents the emis-
sion of fuel tank vapors into the atmosphere. When
fuel evaporates in the fuel tank, the vapors pass
through vent hoses or tubes to an activated carbon
filled evaporative canister. The canister temporarily
holds the vapors. The Powertrain Control Module
(PCM) allows intake manifold vacuum to draw
vapors into the combustion chambers during certain
operating conditions (Fig. 1).All engines use a proportional purge solenoid sys-
tem. The PCM controls vapor flow by operating the
purge solenoid. Refer to Proportional Purge Solenoid
in this section.
NOTE: The evaporative system uses specially man-
ufactured hoses. If they need replacement, only use
fuel resistant hose. Also the hoses must be able to
pass an Ozone compliance test.
NOTE: For more information on Onboard Refueling
Vapor Recovery (ORVR), refer to the Fuel Delivery
section.
RSEVAPORATIVE EMISSIONS25-11
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LEAK DETECTION PUMP
REMOVAL
(1) Disconnect the negative battery cable.
(2) Raise and support the vehicle.
(3) Remove 3 hoses (Fig. 4).
(4) Remove the electrical connector (Fig. 5).
(5) Remove the 3 screws and remove LDP pump.
INSTALLATION
(1) Install LDP.
(2) Install the 3 screws and tighten (Fig. 5).
(3) Install the electrical connector.
(4) Install the 3 hoses (Fig. 4).
(5) Lower vehicle.
(6) Connect the negative battery cable.
ORVR
OPERATION
The emission control principle used in the ORVR
system is that the fuel flowing into the filler tube
(appx. 1º I.D.) creates an aspiration effect which
draws air into the fill tube (Fig. 6). During refueling,
the fuel tank is vented to the vapor canister to cap-
ture escaping vapors. With air flowing into the filler
tube, there are no fuel vapors escaping to the atmo-
sphere. Once the refueling vapors are captured by
the canister, the vehicle's computer controlled purge
system draws vapor out of the canister for the engine
to burn. The vapors flow is metered by the purge
solenoid so that there is no or minimal impact on
driveability or tailpipe emissions.
As fuel starts to flow through the fill tube, it opens
the normally closed check valve and enters the fuel
tank. Vapor or air is expelled from the tank through
the control valve to the vapor canister. Vapor is
absorbed in the canister until vapor flow in the lines
stops, either following shut-off or by having the fuel
level in the tank rise high enough to close the control
valve. The control valve(Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/FUEL TANK - OPERATION)
contains a float that rises to seal the large diameter
vent path to the canister. At this point in the fueling
of the vehicle, the tank pressure increases, the check
valve closes (preventing tank fuel from spitting back
at the operator), and fuel then rises up the filler tube
to shut-off the dispensing nozzle.
If the engine is shut-off while the On-Board diag-
nostics test is running, low level tank pressure can
be trapped in the fuel tank and fuel can not be added
to the tank until the pressure is relieved. This is due
to the leak detection pump closing the vapor outlet
from the top of the tank and the one-way check valve
not allowing the tank to vent through the fill tube to
atmosphere. Therefore, when fuel is added, it will
back-up in the fill tube and shut off the dispensing
nozzle. The pressure can be eliminated in two ways:
1. Vehicle purge must be activated and for a long
enough period to eliminate the pressure. 2. Removing
the fuel cap and allowing enough time for the system
to vent thru the recirulation tube.
Fig. 4 LDP LOCATION
Fig. 5 LDP REMOVAL/INSTALLATION
25 - 14 EVAPORATIVE EMISSIONSRS
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REMOVAL
REMOVAL
(1) Raise and support the vehicle.
(2) Remove the 2 hoses (Fig. 12).
(3) Remove bolt.
(4) Pull canister rearward to remove.
REMOVAL - REAR EVAP CANISTER
(1) Raise and support the vehicle.
(2) Remove 3 hoses (Fig. 13).
(3) Remove the bolt.
(4) Pull rearward to remove canister.
INSTALLATION
INSTALLATION
(1) Install canister arrow heads into the rubber
gromments (Fig. 14)(2) Install bolt and tighten.
(3) Install hoses.
(4) Lower vehicle.
INSTALLATION - REAR EVAP CANISTER
(1) Install canister arrow heads into the rubber
gromments (Fig. 15).
(2) Install bolt and tighten.
(3) Install hoses.
(4) Lower vehicle.
Fig. 14 FRONT EVAP CANISTER BRACKET
Fig. 15 REAR EVAP CANISTER BRACKET
RSEVAPORATIVE EMISSIONS25-19
VAPOR CANISTER (Continued)
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(2) Disconnect the fresh air makeup hose on rear
valve cover.
(3) Remove the air box bolt.
(4) Remove the hose clamp at throttle body.
(5) Unlatch 2 clamps for air box cover.
(6) Remove air box cover.
(7) Disconnect the washer fluid fill hose.
(8) Remove air box.
(9) Remove the 2 bolts at the EGR valve.
(10) Remove the 2 bolts at the intake manifold.
(11) Remove front EGR tube.
REMOVAL - REAR TUBE - 3.5L
(1) Remove the battery, refer to the Battery sec-
tion.
(2) Remove the Battery tray/vacuum reservoir.
(3) Remove the speed control servo and bracket
and relocate.
(4) Remove the 2 bolts from the EGR valve.
(5) Remove the 2 bolts from the rear cylinder
head.
(6) Remove the EGR rear tube.
INSTALLATION
INSTALLATION - 2.4L
(1) Loose install EGR tube and gasket with attach-
ing bolts at intake manifold.
(2) Loose install EGR tube and gasket with attach-
ing bolts at EGR valve.
(3) Tighten bolts to EGR valve to 11.9 N´m (105
20 ins. lbs.).
(4) Tighten bolts to Intake manifold to 11.9 N´m
(105 20 ins. lbs.).
INSTALLATION - FRONT TUBE - 3.5L
(1) Install front EGR tube and gaskets.
(2) Install the 2 bolts at the EGR valve.
(3) Install the 2 bolts at the intake manifold.
(4) Tighten all 4 bolts.
(5) Install air box.
(6) Connect the washer fluid fill hose.
(7) Install air box cover.
(8) Latch 2 clamps for air box cover.
(9) Install the hose clamp at throttle body.
(10) Install the air box bolt.
(11) Connect the fresh air makeup hose on rear
valve cover.
(12) Connect the negative battery cable.
INSTALLATION - REAR TUBE - 3.5L
(1) Install the EGR rear tube.
(2) Install the 2 bolts to the rear cylinder head.
(3) Install the 2 bolts to the EGR valve.
(4) Tighten the 4 bolts.(5) Install the speed control servo and bracket,
refer to the speed control section.
(6) Install the Battery tray/vacuum reservoir refer
to the battery section.
(7) Install the battery, refer to the Battery section.
VA LV E
DESCRIPTION
The EGR system consists of:
²EGR tube (connects a passage in the intake
manifold to the exhaust port in the cylinder head)
²EGR valve
²Electronic EGR Transducer
²Connecting hoses
OPERATION
Refer to Monitored Systems - EGR Monitor in this
group for more information.
The engines use Exhaust Gas Recirculation (EGR)
systems. The EGR system reduces oxides of nitrogen
(NOx) in engine exhaust and helps prevent detona-
tion (engine knock). Under normal operating condi-
tions, engine cylinder temperature can reach more
than 3000ÉF. Formation of NOx increases proportion-
ally with combustion temperature. To reduce the
emission of these oxides, the cylinder temperature
must be lowered. The system allows a predetermined
amount of hot exhaust gas to recirculate and dilute
Fig. 1 EGR VALVE AND TUBE 2.4L
1 - EGR Tube
2 - EGR Valve
RSEXHAUST GAS RECIRCULATION25-21
TUBE (Continued)
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EXHAUST GAS RECIRCULATION
TABLE OF CONTENTS
page page
EXHAUST GAS RECIRCULATION
DESCRIPTION..........................3
OPERATION............................3
VA LV E
DESCRIPTION..........................3
OPERATION............................3REMOVAL.............................4
INSTALLATION..........................4
VALVE COOLER
DESCRIPTION..........................4
REMOVAL.............................4
INSTALLATION..........................5
EXHAUST GAS
RECIRCULATION
DESCRIPTION
The EGR system reduces oxides of nitrogen (NOx)
in the engine exhaust. This is accomplished by allow-
ing a predetermined amount of hot exhaust gas to
recirculate and dilute the incoming fuel/air mixture.
A malfunctioning EGR system can cause engine
stumble, sags, or hesitation, rough idle, engine stall-
ing and poor driveability.
OPERATION
The system consists of:
²An EGR valve assembly. The valve is located on
the rear of the engine above the exhaust manfiold.
²An EGR solenoid.The EGR solenoid controls the
ªon timeº of the EGR valve.
²The ECM operates the EGR solenoid. The ECM
is located inside the vehicle under the instrument
panel.
²An EGR tube connects a passage in the EGR
valve to the rear of the exhaust manifold.
²The vacuum pump supplies vacuum for the EGR
solenoid and the EGR valve. This pump also supplies
vacuum for operation of the power brake boosterb
and the heating and air conditioning system. The
pump is located internally in the front of the engine
block and is driven by the crankshaft gear.²Vacuum lines and hoses connect the various
components.
When the ECM supplies a variable ground signal
to the EGR solenoid, EGR system operation starts to
occur. The ECM will monitor and determine when to
supply and remove this variable ground signal. This
will depend on inputs from the engine coolant tem-
perature, throttle position and engine speed sensors.
When the variable ground signal is supplied to the
EGR solenoid, vacuum from the vacuum pump will
be allowed to pass through the EGR solenoid and on
to the EGR valve with a connecting hose.
Exhaust gas recirculation will begin in this order
when:
²The ECM determines that EGR system opera-
tion is necessary.
²The engine is running to operate the vacuum
pump.
²A variable ground signal is supplied to the EGR
solenoid.
²Variable vacuum passes through the EGR sole-
noid to the EGR valve.
²The inlet seat (poppet valve) at the bottom of
the EGR valve opens to dilute and recirculate
exhaust gas back into the intake manifold.
The EGR system will be shut down by the ECM
after 60 seconds of continuous engine idling to
improve idle quality.
RGEXHAUST GAS RECIRCULATION25a-3
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