2003 CHRYSLER CARAVAN low oil pressure

CYLINDER BORE
NOTE: The cylinder bores should be measured at
normal room temperature, 21ÉC (70ÉF).
The cylinder walls should be checked for out-of-
round and taper with Tool C119 or equivalent (Fig.
45) (Refer to 9 - ENGINE - SPECIFICATIONS). If
the cylinder walls are badly scuffed or scored, the
cylinder block should be replaced, and new pistons
and rings fitted.
Measure the cylinder bore at three levels in direc-
tions A and B (Fig. 45). Top measurement should be
10 mm (3/8 in.) down and bottom measurement
should be 10 mm (3/8 in.) up from bottom of bore.
(Refer to 9 - ENGINE - SPECIFICATIONS).
HYDRAULIC LIFTERS (CAM IN
BLOCK)
DESCRIPTION
The hydraulic lifters are a roller type design and
are positioned in the cylinder block. The lifters are
aligned and retained by a yoke and a retainer (Fig.
47).Lifter alignment is maintained by machined flats
on lifter body. Lifters are fitted in pairs into six
aligning yokes. The aligning yokes are secured by a
yoke retainer (Fig. 47).
DIAGNOSIS AND TESTING - HYDRAULIC
LIFTERS
HYDRAULIC LIFTERS DIAGNOSIS - PRELIMINARY
STEP
Before disassembling any part of the engine to cor-
rect lifter noise, check the engine oil pressure. (Refer
to 9 - ENGINE/LUBRICATION - DIAGNOSIS AND
TESTING)
Check engine oil level. The oil level in the pan
should never be above the MAX mark on dipstick, or
below the MIN mark. Either of these two conditions
could cause noisy lifters.
OIL LEVEL TOO HIGH
If oil level is above the MAX mark on dipstick, it is
possible for the connecting rods to dip into the oil
while engine is running and create foaming. Foam in
oil pan would be fed to the hydraulic lifters by the oil
pump causing them to become soft and allow valves
to seat noisily.
OIL LEVEL TOO LOW
Low oil level may allow pump to take in air which
when fed to the lifters it causes them to become soft
and allows valves to seat noisily. Any leaks on intake
side of pump, through which air can be drawn, will
create the same lifter noise. Check the lubrication
system from the intake strainer to the oil pump
cover, including the relief valve retainer cap. When
lifter noise is due to aeration, it may be intermittent
or constant, and usually more than one lifter will be
noisy. When oil level and leaks have been corrected,
the engine should be operated at fast idle to allow all
of the air inside of the lifters to be bled out.
VALVE TRAIN NOISE
To determine source of valve train noise, operate
engine at idle with cylinder head covers removed and
listen for source of the noise.
NOTE: Worn valve guides or cocked springs are
sometimes mistaken for noisy lifters. If such is the
case, noise may be dampened by applying side
thrust on the valve spring. If noise is not apprecia-
bly reduced, it can be assumed the noise is in the
tappet. Inspect the rocker arm push rod sockets
and push rod ends for wear.
Fig. 45 Checking Cylinder Bore Size
RSENGINE 3.3/3.8L9 - 113
ENGINE BLOCK (Continued)
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LUBRICATION
DESCRIPTION
The lubrication system is a full flow filtration pres-
sure feed type. The oil pump is mounted in the tim-
ing chain cover and is driven by the crankshaft
OPERATION
Oil from the oil pan is pumped by a internal gear
type oil pump directly coupled to the crankshaft. The
pressure is regulated by a relief valve located in the
timing chain cover. The oil is pumped through an oil
filter and feeds a main oil gallery. This oil gallery
feeds oil under pressure to the main and rod bear-
ings, camshaft bearings. Passages in the cylinder
block feed oil to the hydraulic lifters and rocker shaft
brackets which feeds the rocker arm pivots (Fig. 94).
DIAGNOSIS AND TESTING - ENGINE OIL
PRESSURE
(1) Disconnect and remove oil pressure switch
(Refer to 9 - ENGINE/LUBRICATION/OIL PRES-
SURE SENSOR/SWITCH - REMOVAL).
(2) Install Special Tools C-3292 Gauge with 8406
Adaptor. For Special Tool identification, (Refer to 9 -
ENGINE - SPECIAL TOOLS).
(3) Start engine and record oil pressure. Refer to
Oil Pressure in Engine Specifications for the correct
pressure (Refer to 9 - ENGINE - SPECIFICATIONS).
Fig. 94 Engine Oiling System
1 - OIL SUPPLY FOR BALL SOCKET THROUGH PUSH ROD 7 - OUTER ROTOR
2 - OIL SUPPLY PASSAGE FROM SHAFT TO ROCKER ARM 8 - INNER ROTOR
3 - ROCKER SHAFT 9 - RELIEF VALVE
4 - OIL FLOWS TO ONLY ONE PEDASTAL ON EACH HEAD; THIRD
FROM REAR ON RIGHT HEAD, THIRD FROM FRONT ON LEFT
HEAD10 - OIL PAN
5 - ROCKER SHAFT TOWER 11 - OIL SCREEN
6 - CRANKSHAFT 12 - OIL PUMP CASE
9 - 136 ENGINE 3.3/3.8LRS
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OIL COOLER & LINES
DESCRIPTION
An engine oil cooler is used on 3.3/3.8L engines
(Heavy Duty Cooling Only) (Fig. 98). The cooler is a
coolant-to-oil type and mounted between the oil filter
and engine block.
OPERATION
Engine oil travels from the oil filter and into the
oil cooler. Engine oil then exits the cooler into the
main gallery. Engine coolant flows into the cooler
from the heater return tube and exits into the water
pump inlet.
REMOVAL
(1) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE - COOLING SYSTEM
DRAINING).
(2) Disconnect oil cooler inlet and outlet hoses
(Fig. 97).
(3) Remove oil filter.
(4) Remove oil cooler attachment fitting (Fig. 98).
(5) Remove oil cooler.
INSTALLATION
(1) Lubricate seal and position oil cooler to connec-
tor fitting on oil filter adapter (Fig. 98).NOTE: Position the flat side of oil cooler parallel to
oil pan rail.
(2) Install oil cooler attachment fitting and tighten
to 27 N´m (20 ft. lbs.) (Fig. 98).
(3) Install oil filter.
(4) Connect oil cooler inlet and outlet hoses (Fig.
97).
Fig. 96 Engine Oil Level Dipstick and Fill Locations
1 - COOLANT RECOVERY CONTAINER 3 - ENGINE OIL LEVEL DIPSTICK
2 - ENGINE OIL FILL CAP 4 - RADIATOR PRESSURE CAP
Fig. 97 Engine Oil Cooler Hoses
1 - OIL COOLER INLET TUBE
2 - INLET HOSE
3 - OIL COOLER OUTLET TUBE
4 - OUTLET HOSE
5 - WATER PUMP INLET TUBE
9 - 138 ENGINE 3.3/3.8LRS
OIL (Continued)
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(5) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE - COOLING SYSTEM
FILLING).
OIL FILTER
REMOVAL
CAUTION: When servicing the oil filter avoid
deforming the filter can by installing the remove/in-
stall tool band strap against the can-to-base lock
seam. The lock seam joining the can to the base is
reinforced by the base plate.
(1) Using suitable oil filter wrench, turn filter
counterclockwise to remove from oil filter adapter
(Fig. 99). Properly discard used oil filter.
INSTALLATION
(1) Wipe oil filter adapter base clean and inspect
gasket contact surface.
(2) Lubricate gasket of new filter with clean
engine oil.
(3) Install new filter until gasket contacts base
(Fig. 99). Tighten filter 1 turn or 20 N´m (15 ft. lbs.).
Use filter wrench if necessary.
(4) Start engine and check for leaks.
OIL FILTER ADAPTER
REMOVAL
(1) Raise vehicle on hoist.
(2) Remove the oil filter.
(3) Disconnect oil pressure switch electrical con-
nector.
(4) Remove oil filter adapter attaching bolts (Fig.
99).
(5) Remove oil filter adapter and seal (Fig. 99).
INSTALLATION
(1) Clean oil filter adapter and install new seal.
(2) Position adapter on engine block and install
bolts (Fig. 99).
(3) Tighten adapter bolts to 28 N´m (250 in. lbs.).
(4) Connect oil pressure switch electrical connector
(Fig. 99).
(5) Install the oil filter.
(6) Lower vehicle on hoist.
(7) Start engine and allow to run approximately 2
minutes.
(8) Turn off engine and check oil level. Adjust oil
level as necessary.
Fig. 98 Engine Oil Cooler - 3.3/3.8L (Heavy Duty
Cooling)
1 - OIL FILTER ADAPTER
2 - CONNECTOR
3 - ENGINE OIL COOLER
4 - OIL COOLER ATTACHMENT FITTING
5 - OIL FILTER
Fig. 99 OIL FILTER ADAPTER
1 - SEAL
2 - OIL FILTER ADAPTER
3 - OIL FILTER
4 - BOLT
5 - OIL PRESSURE SWITCH
6 - BOLT
RSENGINE 3.3/3.8L9 - 139
OIL COOLER & LINES (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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(5) Install outer rotor into chain case cover. Press
rotor to one side with fingers and measure clearance
between rotor and chain case cover (Fig. 109). If mea-
surement is 0.39 mm (0.015 in.) or more, replace
chain case cover, only if outer rotor is in specification.
(6) Install inner rotor into chain case cover. If
clearance between inner and outer rotors (Fig. 110) is
0.203 mm (0.008 in.) or more, replace both rotors.
(7) Place a straightedge across the face of the
chain case cover, between bolt holes. If a feeler gauge
of 0.10 mm (0.004 in.) or more can be inserted
between rotors and the straightedge, replace pump
assembly (Fig. 111).ONLYif rotors are in specs.
(8) Remove oil pressure relief valve. (Refer to 9 -
ENGINE/LUBRICATION/OIL PRESSURE RELIEF
VALVE - REMOVAL)
(9) Inspect oil pressure relief valve and bore.
Inspect for scoring, pitting and free valve operationin bore (Fig. 112). Small marks may be removed with
400-grit wet or dry sandpaper.
(10) The relief valve spring has a free length of
approximately 49.5 mm (1.95 inches) it should test
between 19.5 and 20.5 pounds when compressed to
34 mm (1-11/32 inches). Replace spring that fails to
meet specifications.
(11) If oil pressure is low and pump is within spec-
ifications, inspect for worn engine bearings or other
reasons for oil pressure loss.
ASSEMBLY
(1) Assemble pump, using new parts as required.
Install the inner rotor with chamfer facing the
cast iron oil pump cover.
(2) Prime oil pump before installation by filling
rotor cavity with engine oil.
Fig. 106 Checking Oil Pump Cover Flatness
1 - FEELER GAUGE
2 - OIL PUMP COVER
3 - STRAIGHT EDGE
Fig. 107 Measuring Outer Rotor Thickness
Fig. 108 Measuring Inner Rotor Thickness
Fig. 109 Measuring Outer Rotor Clearance in
Housing
1 - FEELER GAUGE
2 - OUTER ROTOR
RSENGINE 3.3/3.8L9 - 143
OIL PUMP (Continued)
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(3) Install cover and tighten screws to 12 N´m (105
in. lbs.).
(4) If removed, install the oil pressure relief valve.
(Refer to 9 - ENGINE/LUBRICATION/OIL PRES-
SURE RELIEF VALVE - INSTALLATION)
INSTALLATION
(1) Install oil pump. (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PUMP - ASSEMBLY)
(2) Install timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION) and oil pan (Refer to 9
- ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
INTAKE MANIFOLD
DESCRIPTION
The intake system is made up of an upper and
lower intake manifold. The upper intake manifold is
made of a composite for both the 3.3L engine and for
the 3.8L engine (Fig. 117). The lower intake manifold
is common between the two engines (Fig. 121). It also
provides coolant crossover between cylinder heads
and houses the coolant thermostat (Fig. 121).
The intake manifold utilizes a compact design with
very low restriction and outstanding flow balance.
This design allows the engine to perform with a wide
torque curve while increasing higher rpm horse-
power.
If, for some reason, the molded-in vacuum ports
break, the composite manifold can be salvaged. The
vacuum ports are designed to break at the shoulder,
if overloaded. Additional material in the shoulder
area provides sufficient stock to repair. For more
information and procedure, (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - STANDARD
PROCEDURE). Also, if the special screws that attach
the MAP sensor, power steering reservoir, throttle
cable bracket, and the EGR tube become stripped, an
oversized screw is available to repair the stripped-out
condition. For more information and procedure,
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - STANDARD PROCEDURE)
Fig. 110 Measuring Clearance Between Rotors
1 - FEELER GAUGE
2 - INNER ROTOR
3 - OUTER ROTOR
Fig. 111 Measuring Clearance Over Rotors
1 - FEELER GAUGE
2 - STRAIGHT EDGE
Fig. 112 Oil Pressure Relief Valve
1 - RELIEF VALVE
2 - SPRING
3 - RETAINER CAP
9 - 144 ENGINE 3.3/3.8LRS
OIL PUMP (Continued)
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(7) Disconnect the manifold absolute pressure
(MAP) sensor electrical connector.
(8) Disconnect the vapor purge vacuum hose from
throttle body.
(9) Disconnect the PCV hose (Fig. 114).
(10) Remove the power steering reservoir attach-
ing bolts and only loosen the nut (Fig. 115). Lift res-
ervoir up to disengage lower mount from stud. Set
reservoir aside.Do notdisconnect hose.
(11) Disconnect the brake booster and leak detec-
tion pump (LDP) hoses from intake manifold (Fig.
116).
(12) Remove intake manifold bolts and remove the
manifold (Fig. 117).
(13) Cover the lower intake manifold with a suit-
able cover while the upper manifold is removed.
(14) Clean and inspect the upper intake manifold
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - CLEANING) and (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - INSPECTION).
CLEANING
(1) Discard gasket(s).
(2) Clean all sealing surfaces.
INSPECTION
Check manifold for:
²Damage and cracks.
Fig. 113 Intake Manifold Port Repair
1 - BRAKE BOOSTER PORT = 1/49±18 NPT PIPE TAP
1 - LDP/SPEED CONTROL PORT = 1/89±18 NPT PIPE TAP
2 - DRILL BIT = 7/169BRAKE BOOSTER PORT
2 - DRILL BIT = 11/329LDP/SPEED CONTROL PORT
3 - INTAKE MANIFOLD
Fig. 114 PCV & HOSE
1 - HOSE - PCV
2 - P C V VA LV E
Fig. 115 POWER STEERING FLUID RESERVOIR
1 - POWER STEERING RESERVOIR
2 - BOLT - RESERVOIR TO MANIFOLD
3 - NUT - RESERVOIR TO COIL BRACKET
9 - 146 ENGINE 3.3/3.8LRS
INTAKE MANIFOLD - UPPER (Continued)
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