check engine light CHRYSLER CARAVAN 2003 Owner's Manual

DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - PERFORMANCE
CONDITION POSSIBLE CAUSE CORRECTION
ENGINE WILL NOT START 1. Weak battery. 1. Test battery. Charge or replace
as necessary. (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM -
DIAGNOSIS AND TESTING)
2. Corroded or loose battery
connections.2. Clean and tighten battery
connections. Apply a coat of light
mineral grease to terminals.
3. Faulty starter. 3. Test starting system. (Refer to 8 -
ELECTRICAL/STARTING -
DIAGNOSIS AND TESTING)
4. Faulty coil(s) or control unit. 4. Test and replace as needed.
(Refer to Appropriate Diagnostic
Information)
5. Incorrect spark plug gap. 5. Set gap. (Refer to 8 -
ELECTRICAL/IGNITION CONTROL
- SPECIFICATIONS)
6. Contamination in fuel system. 6. Clean system and replace fuel
filter.
7. Faulty fuel pump. 7. Test fuel pump and replace as
needed. (Refer to Appropriate
Diagnostic Information)
8. Incorrect engine timing. 8. Check for a skipped timing
belt/chain.
ENGINE STALLS OR IDLES
ROUGH1. Idle speed too low. 1. Test minimum air flow. (Refer to
Appropriate Diagnostic Information)
2. Incorrect fuel mixture. 2. (Refer to Appropriate Diagnostic
Information)
3. Intake manifold leakage. 3. Inspect intake manifold, manifold
gasket, and vacuum hoses.
4. Faulty ignition coil(s). 4. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)
9 - 78 ENGINE 3.3/3.8LRS
ENGINE 3.3/3.8L (Continued)
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CONDITION POSSIBLE CAUSES CORRECTION
OIL CONSUMPTION OR SPARK
PLUGS FOULED1. PCV system malfunction. 1. Check system and repair as
necessary. (Refer to 25 -
EMISSIONS CONTROL/
EVAPORATIVE EMISSIONS/PCV
VALVE - DIAGNOSIS AND
TESTING)
2. Worn, scuffed or broken rings. 2. Hone cylinder bores. Install new
rings.
3. Carbon in oil ring slots. 3. Install new rings.
4. Rings fitted too tightly in grooves. 4. Remove rings and check
grooves. If groove is not proper
width, replace piston.
5. Worn valve guide(s). 5. Replace cylinder head assembly.
6. Valve stem seal(s) worn or
damaged.6. Replace seal(s).
DIAGNOSIS AND TESTING - ENGINE OIL LEAK
INSPECTION
Begin with a thorough visual inspection of the
engine, particularly at the area of the suspected leak.
If an oil leak source is not readily identifiable, the
following steps should be followed:
(1) Do not clean or degrease the engine at this
time because some solvents may cause rubber to
swell, temporarily stopping the leak.
(2) Add an oil soluble dye (use as recommended by
manufacturer). Start the engine and let idle for
approximately 15 minutes. Check the oil dipstick to
make sure the dye is thoroughly mixed as indicated
with a bright yellow color under a black light.
(3) Using a black light, inspect the entire engine
for fluorescent dye, particularly at the suspected area
of oil leak. If the oil leak is found and identified,
repair as necessary.
(4) If dye is not observed, drive the vehicle at var-
ious speeds for approximately 24 km (15 miles), and
repeat inspection.
(5)If the oil leak source is not positively
identified at this time, proceed with the air leak
detection test method as follows:
²Disconnect the fresh air hose (make-up air) at
the cylinder head cover and plug or cap the nipple on
the cover.
²Remove the PCV valve hose from the cylinder
head cover. Cap or plug the PCV valve nipple on the
cover.
²Attach an air hose with pressure gauge and reg-
ulator to the dipstick tube.
CAUTION: Do not subject the engine assembly to
more than 20.6 kpa (3 PSI) of test pressure.²Gradually apply air pressure from 1 psi to 2.5
psi maximum while applying soapy water at the sus-
pected source. Adjust the regulator to the suitable
test pressure that provides the best bubbles which
will pinpoint the leak source. If the oil leak is
detected and identified, repair per service manual
procedures.
²If the leakage occurs at the crankshaft rear oil
seal area, refer to the section, Inspection for Rear
Seal Area Leak.
(6) If no leaks are detected, turn off the air supply.
Remove the air hose, all plugs, and caps. Install the
PCV valve and fresh air hose (make-up air). Proceed
to next step.
(7) Clean the oil off the suspect oil leak area using
a suitable solvent. Drive the vehicle at various
speeds approximately 24 km (15 miles). Inspect the
engine for signs of an oil leak by using a black light.
NOTE: If oil leakage is observed at the dipstick tube
to block location; remove the tube, clean and reseal
using MoparTStud & Bearing Mount (press fit tube
applications only), and for O-ring style tubes,
remove tube and replace the O-ring seal.
INSPECTION FOR REAR SEAL AREA LEAKS
Since it is sometimes difficult to determine the
source of an oil leak in the rear seal area of the
engine, a more involved inspection is necessary. The
following steps should be followed to help pinpoint
the source of the leak.
If the leakage occurs at the crankshaft rear oil seal
area:
(1) Disconnect the battery.
(2) Raise the vehicle.
9 - 82 ENGINE 3.3/3.8LRS
ENGINE 3.3/3.8L (Continued)
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(3) Remove torque converter or clutch housing
cover and inspect rear of block for evidence of oil.
Use a black light to check for the oil leak. If a leak is
present in this area, remove transmission for further
inspection.
(a) Circular spray pattern generally indicates
seal leakage or crankshaft damage.
(b) Where leakage tends to run straight down,
possible causes are a porous block, oil gallery cup
plug, bedplate to cylinder block mating surfaces
and seal bore. See proper repair procedures for
these items.
(4) If no leaks are detected, pressurize the crank-
case as previously described.
CAUTION: Do not exceed 20.6 kPa (3 psi).
(5) If the leak is not detected, very slowly turn the
crankshaft and watch for leakage. If a leak is
detected between the crankshaft and seal while
slowly turning the crankshaft, it is possible the
crankshaft seal surface is damaged. The seal area on
the crankshaft could have minor nicks or scratches
that can be polished out with emery cloth.
CAUTION: Use extreme caution when crankshaft
polishing is necessary to remove minor nicks and
scratches. The crankshaft seal flange is especially
machined to complement the function of the rear oil
seal.
(6) For bubbles that remain steady with shaft
rotation, no further inspection can be done until dis-
assembled.
(7) After the oil leak root cause and appropriate
corrective action have been identified, replace compo-
nent(s) as necessary.
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE TEST
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Check engine oil level and add oil if necessary.
(2) Drive the vehicle until engine reaches normal
operating temperature. Select a route free from traf-
fic and other forms of congestion, observe all traffic
laws, and accelerate through the gears several times
briskly.
(3) Remove all spark plugs from engine. As spark
plugs are being removed, check electrodes for abnor-
mal firing indicators fouled, hot, oily, etc. Record cyl-
inder number of spark plug for future reference.(4) Remove the Auto Shutdown (ASD) relay from
the PDC.
(5) Be sure throttle blade is fully open during the
compression check.
(6) Insert compression gauge adaptor Special Tool
8116 or the equivalent, into the #1 spark plug hole in
cylinder head. Connect the 0±500 psi (Blue) pressure
transducer (Special Tool CH7059) with cable adap-
tors to the DRBIIIt. For Special Tool identification,
(Refer to 9 - ENGINE - SPECIAL TOOLS).
(7) Crank engine until maximum pressure is
reached on gauge. Record this pressure as #1 cylin-
der pressure.
(8) Repeat the previous step for all remaining cyl-
inders.
(9) Compression should not be less than 689 kPa
(100 psi) and not vary more than 25 percent from cyl-
inder to cylinder.
(10) If one or more cylinders have abnormally low
compression pressures, repeat the compression test.
(11) If the same cylinder or cylinders repeat an
abnormally low reading on the second compression
test, it could indicate the existence of a problem in
the cylinder in question.The recommended com-
pression pressures are to be used only as a
guide to diagnosing engine problems. An engine
should not be disassembled to determine the
cause of low compression unless some malfunc-
tion is present.
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE TEST
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing).
²Leaks between adjacent cylinders or into water
jacket.
²Any causes for combustion/compression pressure
loss.
WARNING: DO NOT REMOVE THE PRESSURE CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM COOLANT CAN
OCCUR.
Check the coolant level and fill as required. DO
NOT install the pressure cap.
Start and operate the engine until it attains nor-
mal operating temperature, then turn the engine
OFF.
Clean spark plug recesses with compressed air.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
RSENGINE 3.3/3.8L9-83
ENGINE 3.3/3.8L (Continued)
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(1) Inspect air cleaner, induction system and
intake manifold to insure system is dry and clear of
foreign material.
(2) Remove negative battery cable.
(3) Place a shop towel around the spark plugs
when removing them from the engine. This will catch
any fluid that may possibly be in the cylinder under
pressure.
(4) With all spark plugs removed, rotate engine
crankshaft using a breaker bar and socket.
(5) Identify the fluid in the cylinder(s) (i.e., cool-
ant, fuel, oil or other).
(6) Make sure all fluid has been removed from the
cylinders. Inspect engine for damage (i.e., connecting
rods, pistons, valves, etc.)
(7) Repair engine or components as necessary to
prevent this problem from re-occurring.
CAUTION: Squirt approximately one teaspoon of oil
into the cylinders, rotate engine to lubricate the cyl-
inder walls to prevent damage on restart.
(8) Install new spark plugs.
(9) Drain engine oil and remove oil filter.
(10) Install a new oil filter.
(11) Fill engine with specified amount of approved
oil.
(12) Connect negative battery cable.
(13) Start engine and check for any leaks.
STANDARD PROCEDURE - REPAIR OF
DAMAGED OR WORN THREADS
Damaged or worn threads (excluding spark plug
and camshaft bearing cap attaching threads) can be
repaired. Essentially, this repair consists of drilling
out worn or damaged threads, tapping the hole with
a special Heli-Coil Tap, (or equivalent) and installing
an insert into the tapped hole. This brings the hole
back to its original thread size.
CAUTION: Be sure that the tapped holes maintain
the original center line.
Heli-Coil tools and inserts are readily available
from automotive parts jobbers.
STANDARD PROCEDURE - ENGINE CORE AND
OIL GALLERY PLUGS
Using a blunt tool such as a drift and a hammer,
strike the bottom edge of the cup plug. With the cup
plug rotated, grasp firmly with pliers or other suit-
able tool and remove plug (Fig. 5).
CAUTION: Do not drive cup plug into the casting as
restricted cooling can result and cause serious
engine problems.Thoroughly clean inside of cup plug hole in cylin-
der block or head. Be sure to remove old sealer.
Lightly coat inside of cup plug hole with Mopart
Stud and Bearing Mount. Make certain the new plug
is cleaned of all oil or grease. Using proper drive
plug, drive plug into hole so that the sharp edge of
the plug is at least 0.5 mm (0.020 in.) inside the
lead-in chamfer.
It is not necessary to wait for curing of the sealant.
The cooling system can be refilled and the vehicle
placed in service immediately.
REMOVAL - ENGINE ASSEMBLY
(1) Perform fuel pressure release procedure (Refer
to 14 - FUEL SYSTEM/FUEL DELIVERY - STAN-
DARD PROCEDURE).
(2) Disconnect negative battery cable.
(3) Remove air cleaner and hoses.
(4) Disconnect the fuel line from fuel rail (Refer to
14 - FUEL SYSTEM/FUEL DELIVERY/QUICK
CONNECT FITTING - STANDARD PROCEDURE).
(5) Remove the wiper module (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS/WIPER MODULE -
REMOVAL).
(6) Block off heater hoses to the rear heater sys-
tem using pinch-off pliers (if equipped).
(7) Drain the cooling system (Refer to 7 - COOL-
ING - STANDARD PROCEDURE).
(8) Disconnect the heater hoses.
(9) Remove the radiator upper support crossmem-
ber (Refer to 23 - BODY/EXTERIOR/GRILLE OPEN-
ING REINFORCEMENT - REMOVAL).
(10) Remove the radiator fans (Refer to 7 - COOL-
ING/ENGINE/RADIATOR FAN - REMOVAL).
Fig. 5 Core Hole Plug Removal
1 - CYLINDER BLOCK
2 - REMOVE PLUG WITH PLIERS
3 - STRIKE HERE WITH HAMMER
4 - DRIFT PUNCH
5 - CUP PLUG
9 - 86 ENGINE 3.3/3.8LRS
ENGINE 3.3/3.8L (Continued)
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REMOVAL
(1) Remove the valve springs. (Refer to 9 -
ENGINE/CYLINDER HEAD/VALVE SPRINGS -
REMOVAL)
(2) Remove the valve stem seal (Fig. 43).
INSTALLATION
(1) Install the valve stem seal squarely over the
valve guide, using the valve stem as a guide (Fig.
43). Do not force the seal against top of the valve
guide.
(2) Install the valve spring. (Refer to 9 - ENGINE/
CYLINDER HEAD/VALVE SPRINGS - INSTALLA-
TION)
ENGINE BLOCK
DESCRIPTION
The cylinder block is made of cast iron and is a
deep skirt design.
STANDARD PROCEDURE - CYLINDER BORE
HONING
(1) Used carefully, the cylinder bore resizing hone,
recommended tool C-823 or equivalent, equipped
with 220 grit stones, is the best tool for this honing
procedure. In addition to deglazing, it will reduce
taper and out-of-round as well as removing light
scuffing, scoring or scratches. Usually a few strokes
will clean up a bore and maintain the required lim-
its.
(2) Deglazing of the cylinder walls may be done
using a cylinder surfacing hone, recommended tool
C-3501 or equivalent, equipped with 280 grit stones,
if the cylinder bore is straight and round. 20±60
strokes depending on the bore condition, will be suf-
ficient to provide a satisfactory surface. Use a light
honing oil.Do not use engine or transmission oil,
mineral spirits or kerosene.Inspect cylinder walls
after each 20 strokes.
(3) Honing should be done by moving the hone up
and down fast enough to get a cross-hatch pattern.
When hone marksintersectat 40-60 degrees, the
cross hatch angle is most satisfactory for proper seat-
ing of rings (Fig. 44).
(4) A controlled hone motor speed between
200±300 RPM is necessary to obtain the proper cross-
hatch angle. The number of up and down strokes per
minute can be regulated to get the desired 40±60
degree angle. Faster up and down strokes increase
the cross-hatch angle.(5) After honing, it is necessary that the block be
cleaned again to remove all traces of abrasive.
CAUTION: Ensure all abrasives are removed from
engine parts after honing. It is recommended that a
solution of soap and hot water be used with a
brush and the parts then thoroughly dried. The bore
can be considered clean when it can be wiped
clean with a white cloth and cloth remains clean.
Oil the bores after cleaning to prevent rusting.
CLEANING
Clean cylinder block thoroughly using a suitable
cleaning solvent.
INSPECTION
ENGINE BLOCK
(1) Clean cylinder block thoroughly and check all
core hole plugs for evidence of leaking.
(2) If new core plugs are to be installed, (Refer to 9
- ENGINE - STANDARD PROCEDURE - ENGINE
CORE AND OIL GALLERY PLUGS).
(3) Examine block and cylinder bores for cracks or
fractures.
(4) Check block deck surfaces for flatness. Deck
surface must be within service limit of 0.1 mm (0.004
in.).
Fig. 44 Cylinder Bore Cross-Hatch Pattern
1 - CROSS-HATCH PATTERN
2 - 40ɱ60É
9 - 112 ENGINE 3.3/3.8LRS
VALVE STEM SEALS (Continued)
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Valve lifter noise ranges from light noise to a
heavy click. A light noise is usually caused by exces-
sive leak-down around the unit plunger which will
necessitate replacing the lifter, or by the plunger par-
tially sticking in the lifter body cylinder. A heavy
click is caused either by a lifter check valve not seat-
ing, or by foreign particles becoming wedged between
the plunger and the lifter body causing the plunger
to stick in the down position. This heavy click will be
accompanied by excessive clearance between the
valve stem and rocker arm as valve closes. In either
case, lifter assembly should be removed for inspec-
tion.
REMOVAL
(1) Remove the cylinder head(s). (Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL)
(2) Remove the yoke retainer and aligning yokes
(Fig. 47).
(3) Remove the hydraulic lifters. If necessary use
Special Tool C-4129, or equivalent to remove lifters
from bores. If lifters are to be reused, identify each
lifter to ensure installation in original location.
INSTALLATION
(1) Lubricate the lifters with engine oil.
NOTE: Position the lifter in bore with the lubrication
hole facing upward (Fig. 46).
(2) Install the hydraulic lifters with the lubrication
hole facing upward towards middle of block (Fig. 46).
Install lifters in original positions, if reused.(3) Install lifter aligning yokes (Fig. 47).
(4) Install yoke retainer and torque screws to 12
N´m (105 in. lbs.) (Fig. 47).
(5) Install the cylinder heads. (Refer to 9 -
ENGINE/CYLINDER HEAD - INSTALLATION)
(6) Start and operate engine. Warm up to normal
operating temperature.
CAUTION: To prevent damage to valve mechanism,
engine must not be run above fast idle until all
hydraulic lifters have filled with oil and have
become quiet.
Fig. 46 LIFTER LUBRICATION HOLE
Fig. 47 Lifter Aligning Yoke and Retainer
1 - YOKE RETAINER
2 - BOLT - YOKE RETAINER
3 - ALIGNING YOKE
4 - HYDRAULIC LIFTER
9 - 114 ENGINE 3.3/3.8LRS
HYDRAULIC LIFTERS (CAM IN BLOCK) (Continued)
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(7) Lower vehicle and install oil dipstick.
(8) Connect negative cable to battery.
(9) Fill crankcase with oil to proper level.
OIL PRESSURE RELIEF VALVE
REMOVAL
(1) Remove oil pan (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PAN - REMOVAL).
(2) Drill a 3.175 mm (1/8 in.) hole in the center of
the retainer cap (Fig. 103). Insert a self-threading
sheet metal screw into the cap.
(3) Using suitable pliers, remove cap and discard.
(4) Remove spring and relief valve (Fig. 103).
INSTALLATION
(1) Clean relief valve, spring and bore.
NOTE: Lubricate relief valve with clean engine oil
before installing.
(2) Install relief valve and spring into housing.
(3) Install new retainer cap until flush with seal-
ing surface.
(4) Install oil pan (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PAN - INSTALLATION).
(5) Fill crankcase with proper oil to correct level.
OIL PRESSURE SWITCH
DESCRIPTION
The engine oil pressure switch is located on the
lower left front side of the engine. It screws into the
oil filter adapter. The normally closed switch provides
an input through a single wire to the low pressure
indicator light on the instrument cluster.
OPERATION
The oil pressure switch provides a ground for the
instrument cluster low oil pressure indicator light.
The switch receives oil pressure input from the
engine main oil gallery. When engine oil pressure is
greater than 27.5 Kpa (4 psi), the switch contacts
open, providing a open circuit to the low pressure
indicator light. For wiring circuits and diagnostic
information, (Refer to Appropriate Wiring/Diagnostic
Information).
REMOVAL
(1) Raise vehicle on hoist.
(2) Disconnect electrical connector from switch.
(3) Remove oil pressure switch (Fig. 104).
INSTALLATION
(1) Install oil pressure switch. Torque oil pressure
switch to 23 N´m (200 in. lbs.) (Fig. 104).
(2) Connect electrical connector to switch.
(3) Lower the vehicle.
(4) Start engine and check for leaks.
(5) Check engine oil level. Adjust as necessary.
Fig. 102 Oil Pan Sealing
1 - SEALER LOCATIONS
Fig. 103 Oil Pressure Relief Valve
1 - RELIEF VALVE
2 - SPRING
3 - RETAINER CAP
RSENGINE 3.3/3.8L9 - 141
OIL PAN (Continued)
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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 (9 in. lbs.) torque.
Inspect all hose connections such as clamps, cou-
plings and fittings to make sure they are secure and
leaks are not present. The component should be
replaced immediately if there is any evidence of deg-
radation that could result in failure.
Never attempt to repair a plastic fuel line/tube.
Replace as necessary.
Avoid contact of any fuel tubes/hoses with other
vehicle components that could cause abrasions or
scuffing. Be sure that the plastic fuel lines/tubes are
properly routed to prevent pinching and to avoid heat
sources.
FUEL PRESSURE REGULATOR
OPERATION
The fuel system uses a nonadjustable pressure reg-
ulator that maintains fuel system pressure at
approximately 400  34 kPa (58  5 psi). The fuel
pressure regulator contains a diaphragm, calibrated
spring and a fuel return valve. The spring pushes
down on the diaphragm and closes off the fuel return
port. System fuel pressure reflects the amount of fuel
pressure required to open the return port.
The pressure regulator is a mechanical device that
is NOT controlled by the PCM or engine vacuum.
REMOVAL
The fuel pressure regulator is part of the fuel
pump module (Fig. 9). Remove the fuel pump module
from the fuel tank to access the fuel pressure regula-
tor. Refer to the Fuel Pump Module removal in this
section.
(1) Spread tangs on pressure regulator retainer.
(2) Pry fuel pressure regulator out of housing.
(3) Ensure both upper and lower O-rings were
removed with regulator.
INSTALLATION
The fuel pressure regulator is part of the fuel
pump module. Remove the fuel pump module from
the fuel tank to access the fuel pressure regulator.Refer to the Fuel Pump Module removal in this sec-
tion.
(1) Lightly lubricate the O-rings with clean engine
oil and place them into opening in pump module (Fig.
9).
(2) Push regulator into opening in pump module.
(3) Fold tangs on regulator retainer over tabs on
housing.
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, for a short while. It is normal for fuel
pressure to drop to zero after cooldown. The fuel
pump relay provides voltage to the fuel pump. The
fuel pump has a maximum deadheaded pressure out-
put of approximately 880 kPa (130 psi). The regula-
tor adjusts fuel system pressure to approximately
400 kpa  34 kpa (58 psi   5 psi).
NOTE: Checkvalve maintains volume of fuel in the
rail and lines, not pressure.
Fig. 9 Fuel Pressure Regulator O-rings
1 - UPPER O-RING
2 - LOWER 0-RING
RSFUEL DELIVERY14-7
FUEL LINES (Continued)
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1 second. Therefore, battery voltage is not supplied to
the fuel pump, ignition coil, fuel injectors and heated
oxygen sensors.
ENGINE START-UP MODE
This is an OPEN LOOP mode. If the vehicle is in
park or neutral (automatic transaxles) or the clutch
pedal is depressed (manual transaxles) the ignition
switch energizes the starter relay when the engine is
not running. The following actions occur when the
starter motor is engaged.
²If the PCM receives the camshaft position sensor
and crankshaft position sensor signals, it energizes
the Auto Shutdown (ASD) relay and fuel pump relay.
If the PCM does not receive both signals within
approximately one second, it will not energize the
ASD relay and fuel pump relay. The ASD and fuel
pump relays supply battery voltage to the fuel pump,
fuel injectors, ignition coil, (EGR solenoid and PCV
heater if equipped) and heated oxygen sensors.
²The PCM energizes the injectors (on the 69É
degree falling edge) for a calculated pulse width until
it determines crankshaft position from the camshaft
position sensor and crankshaft position sensor sig-
nals. The PCM determines crankshaft position within
1 engine revolution.
²After determining crankshaft position, the PCM
begins energizing the injectors in sequence. It adjusts
injector pulse width and controls injector synchroni-
zation by turning the individual ground paths to the
injectors On and Off.
²When the engine idles within  64 RPM of its
target RPM, the PCM compares current MAP sensor
value with the atmospheric pressure value received
during the Ignition Switch On (zero RPM) mode.
Once the ASD and fuel pump relays have been
energized, the PCM determines injector pulse width
based on the following:
²MAP
²Engine RPM
²Battery voltage
²Engine coolant temperature
²Inlet/Intake air temperature (IAT)
²Throttle position
²The number of engine revolutions since cranking
was initiated
During Start-up the PCM maintains ignition tim-
ing at 9É BTDC.
ENGINE WARM-UP MODE
This is an OPEN LOOP mode. The following inputs
are received by the PCM:
²Manifold Absolute Pressure (MAP)
²Crankshaft position (engine speed)
²Engine coolant temperature
²Inlet/Intake air temperature (IAT)²Camshaft position
²Knock sensor
²Throttle position
²A/C switch status
²Battery voltage
²Vehicle speed
²Speed control
²O2 sensors
The PCM adjusts injector pulse width and controls
injector synchronization by turning the individual
ground paths to the injectors On and Off.
The PCM adjusts ignition timing and engine idle
speed. Engine idle speed is adjusted through the idle
air control motor.
CRUISE OR IDLE MODE
When the engine is at operating temperature this
is a CLOSED LOOP mode. During cruising or idle
the following inputs are received by the PCM:
²Manifold absolute pressure
²Crankshaft position (engine speed)
²Inlet/Intake air temperature
²Engine coolant temperature
²Camshaft position
²Knock sensor
²Throttle position
²Exhaust gas oxygen content (O2 sensors)
²A/C switch status
²Battery voltage
²Vehicle speed
The PCM adjusts injector pulse width and controls
injector synchronization by turning the individual
ground paths to the injectors On and Off.
The PCM adjusts engine idle speed and ignition
timing. The PCM adjusts the air/fuel ratio according
to the oxygen content in the exhaust gas (measured
by the upstream and downstream heated oxygen sen-
sor).
The PCM monitors for engine misfire. During
active misfire and depending on the severity, the
PCM either continuously illuminates or flashes the
malfunction indicator lamp (Check Engine light on
instrument panel). Also, the PCM stores an engine
misfire DTC in memory, if 2nd trip with fault.
The PCM performs several diagnostic routines.
They include:
²Oxygen sensor monitor
²Downstream heated oxygen sensor diagnostics
during open loop operation (except for shorted)
²Fuel system monitor
²EGR monitor (if equipped)
²Purge system monitor
²Catalyst efficiency monitor
²All inputs monitored for proper voltage range,
rationality.
RSFUEL INJECTION14-19
FUEL INJECTION (Continued)
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OPERATION
The power steering pump is a constant displace-
ment vane type pump. The 2.4L pump has an inte-
gral fluid reservoir and there is a secondary remote
non-flow reservoir which acts only as a fluid fill and
check point. The 3.3L/3.8L pump houses very little
fluid and is therefore supplied by a remote flow
through reservoir.
WARNING
WARNING: POWER STEERING FLUID, ENGINE
PARTS AND EXHAUST SYSTEM MAY BE
EXTREMELY HOT IF ENGINE HAS BEEN RUNNING.DO NOT START ENGINE WITH ANY LOOSE OR DIS-
CONNECTED HOSES. DO NOT ALLOW HOSES TO
TOUCH HOT EXHAUST MANIFOLD OR CATALYST.
WARNING: FLUID LEVEL SHOULD BE CHECKED
WITH THE ENGINE OFF TO PREVENT PERSONAL
INJURY FROM MOVING PARTS.
CAUTION
CAUTION: When the system is open, cap all open
ends of the hoses, power steering pump fittings or
power steering gear ports to prevent entry of for-
eign material into the components.
STANDARD PROCEDURE - POWER STEERING
PUMP INITIAL OPERATION
WARNING: FLUID LEVEL SHOULD BE CHECKED
AND ADJUSTED WITH ENGINE OFF TO PREVENT
INJURY FROM MOVING ENGINE COMPONENTS.
CAUTION: Use only MoparTAutomatic Transmis-
sion Fluid (MS-9602) in power steering system. Use
of other MoparTpower steering fluids (MS5931 and
MS9933) should be avoided to ensure peak perfor-
mance of the power steering system under all oper-
ating conditions. Do not overfill.
Read the fluid level through the side of the power
steering fluid reservoir. The fluid level should indi-
cateªFILL RANGEºwhen the fluid is at a temper-
ature of approximately 21ÉC to 27ÉC (70ÉF to 80ÉF).
(1) Wipe the filler cap and area clean, then remove
the cap.
(2) Fill the fluid reservoir to the proper level and
let the fluid settle for at least two (2) minutes.
(3) Start the engine and let run for a few seconds,
then turn the engine off.
(4) Add fluid if necessary. Repeat the above steps
until the fluid level remains constant after running
the engine.
(5) Raise the front wheels off the ground.
(6) Start the engine.
(7) Slowly turn the steering wheel right and left,
lightly contacting the wheel stops.
(8) Add fluid if necessary.
(9) Lower the vehicle, then turn the steering wheel
slowly from lock-to-lock.
(10) Stop the engine. Check the fluid level and
refill as required.
(11) If the fluid is extremely foamy, allow the vehi-
cle to stabilize a few minutes, then repeat the above
procedure.
Fig. 1 POWER STEERING PUMP (2.4L)
1 - PULLEY
2 - BRACKET
3 - PRESSURE FITTING
4 - RETURN FITTING
5 - SUPPLY FITTING
Fig. 2 POWER STEERING PUMP (3.3L/3.8L)
1 - SUPPLY FITTING
2 - PRESSURE FITTING
3 - PULLEY
RSPUMP19-37
PUMP (Continued)
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