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SWITCH-OIL PRESSURE
DESCRIPTION
The 3 wire, solid-state engine oil pressure sensor (sending unit) is located in an engine oil pressure gallery.
OPERATION
The oil pressure sensor uses three circuits. They are:
A 5 volt power supply from the Powertrain Control Module (PCM)
A sensor ground through the PCM’s sensor return
A signal to the PCM relating to engine oil pressure
The oil pressure sensor has a 3 wire electrical function very much like the Manifold Absolute Pressure (MAP) sen-
sor. Meaning different pressures relate to different output voltages.
A 5 volt supply is sent to the sensor from the PCM to power up the sensor. The sensor returns a voltage signal
back to the PCM relating to engine oil pressure. This signal is then transferred (bussed) to the instrument panel on
either a CCD or PCI bus circuit (depending on vehicle line) to operate the oil pressure gauge and the check gauges
lamp. Ground for the sensor is provided by the PCM through a low-noise sensor return.
REMOVAL
1. Disconnect the negative cable from the battery.
2. Raise vehicle on hoist.
3. Remove front splash shield.
4. Disconnect oil pressure sender wire (4).
5. Remove the pressure sender (2).
INSTALLATION
1. Install oil pressure sender.
2. Connect oil pressure sender wire.
3. Install front splash shield.
4. Lower vehicle.
5. Connect the negative battery cable.
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PUMP-ENGINE OIL
REMOVAL
1. Remove the oil pan and pick-up tube (Refer to 9 - ENGINE/LUBRICATION/OILPA N - R E M O VA L ) .
2. Remove the timing chain cover (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) -
REMOVAL).
3. Remove the timing chains and tensioners (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - REMOVAL).
4. Remove the four bolts, primary timing chain tensioner and the oil pump.
DISASSEMBLY
1. Remove oil pump cover screws and lift off cover plate.
2. Remove pump inner and outer rotors.
NOTE: Once the oil pressure relief valve, cup plug, and pin are removed, thepump assembly must be
replaced.
3. If it is necessary to remove the pressure relief valve, drive the roll pinfrom pump housing and remove cup plug,
spring and valve.
INSPECTION
CAUTION: Oil pump pressure relief valve and
spring should not be removed from the oil pump.
If these components are disassembled and or
removed from the pump the entire oil pump
assembly must be replaced.
1. Clean all parts thoroughly. Mating surface of the oil
pump housing should be smooth. If the pump cover
is scratched or grooved the oil pump assembly
should be replaced.
2. Lay a straight edge across the pump cover surface
(3). If a 0.025 mm (0.001 in.) feeler gauge (2) can
be inserted between the cover and the straight
edge the oil pump assembly should be replaced.
3. Measure the thickness of the outer rotor. If the
outer rotor thickness measures at 12.005 mm
(0.472 in.) or less the oil pump assembly must be
replaced.
4. Measure the diameter of the outer rotor. If the outer
rotor diameter measures at 85.925 mm (3.382 in.)
or less the oil pump assembly must be replaced.
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5. Measure the thickness of the inner rotor. If the
inner rotor thickness measures at 12.005 mm
(0.472 in.) or less then the oil pump assembly must
be replaced.
6. Slide outer rotor (2) into the body of the oil pump.
Press the outer rotor to one side of the oil pump
body and measure clearance between the outer
rotor and the body. If the measurement is 0.235mm
(0.009 in.) or more the oil pump assembly must be
replaced.
7. Install the inner rotor into the oil pump body. Mea-
sure the clearance between the inner (3) and outer
(1) rotors. If the clearance between the rotors is
.150 mm (0.006 in.) or more the oil pump assembly
must be replaced.
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8. Place a straight edge (1) across the body of the oil
pump (between the bolt holes), if a feeler gauge (2)
of .095 mm (0.0038 in.) or greater can be inserted
between the straightedge and the rotors, the pump
must be replaced.
NOTE: The 3.7L/4.7L Oil pump is released as an
assembly. There are no DaimlerChrysler part num-
bers for Sub-Assembly components. In the event
the oil pump is not functioning or out of specifica-
tion it must be replaced as an assembly.
ASSEMBLY
1. Wash all parts in a suitable solvent and inspect carefully for damage or wear.
2. Install inner and outer rotors
3. Install oil pump cover plate and install cover bolts and tighten them to 12Nꞏm(105in.lbs.).
4. Prime oil pump before installation by filling rotor cavity with engine oil.
5. If oil pressure is low and pump is within specifications, inspect for worn engine bearings or other causes for oil
pressure loss.
INSTALLATION
1. Position the oil pump onto the crankshaft and
install one oil pump retaining bolt.
2. Position the primary timing chain tensioner and
install three retaining bolts.
3. Tighten the oil pump and primary timing chain ten-
sioner retaining bolts to 28 Nꞏm (250 in. lbs.) in the
sequence shown.
4. Install the secondary timing chain tensioners and
timing chains (Refer to 9 - ENGINE/VALVE TIM-
ING/TIMING BELT/CHAIN AND SPROCKETS -
INSTALLATION).
5. Install the timing chain cover (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT / CHAIN COVER(S)
- INSTALLATION).
6. Install the pick-up tube and oil pan (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN -
INSTALLATION).
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FILTER-ENGINE OIL
REMOVAL
All engines are equipped with a high quality full-flow,
disposable type oil filter (1). DaimlerChrysler Corpora-
tion recommends a Mopar
or equivalent oil filter be
used.
1. Position a drain pan under the oil filter.
2. Using a suitable oil filter wrench loosen filter.
3. Rotate the oil filter counterclockwise to remove it
from the cylinder block oil filter boss.
4. When filter separates from cylinder block oil filter
boss, tip gasket end upward to minimize oil spill.
Remove filter from vehicle.
NOTE: Make sure filter gasket was removed with
filter.
5. With a wiping cloth, clean the gasket sealing sur-
face of oil and grime.
INSTALLATION
1. Lightly lubricate oil filter gasket (2) with engine oil.
2. Thread filter (3) onto adapter nipple. When gasket
makes contact with sealing surface, hand tighten
filter one full turn, do not over tighten.
3. Add oil, verify crankcase oil level and start engine.
Inspect for oil leaks.
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OIL
STANDARD PROCEDURE - ENGINE OIL SERVICE
The engine oil level indicator (1) is located at the right
rear of the engine on the 3.7L/4.7L engines.
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil, pressure loss or oil foaming can result.
Inspect engine oil level approximately every 800 kilometers (500 miles).Unless the engine has exhibited loss of oil
pressure, run the engine for about five minutes before checking oil level.Checking engine oil level on a cold engine
is not accurate.
To ensure proper lubrication of an engine, the engine oil must be maintained at an acceptable level. The acceptable
levels are indicated between the ADD and SAFE marks on the engine oil dipstick.
1. Position vehicle on level surface.
2. With engine OFF, allow approximately ten minutes for oil to settle to bottom of crankcase, remove engine oil
dipstick.
3. Wipe dipstick clean.
4. Install dipstick and verify it is seated in the tube.
5. Remove dipstick, with handle held above the tip, take oil level reading.
6. Add oil only if level is below the ADD mark on dipstick.
ENGINE OIL CHANGE
Change engine oil at mileage and time intervals described in Maintenance Schedules.
Run engine until achieving normal operating temperature.
1. Position the vehicle on a level surface and turn engine off.
2. Hoist and support vehicle on safety stands.
3. Remove oil fill cap.
4. Place a suitable drain pan under crankcase drain.
5. Remove drain plug from crankcase and allow oil to drain into pan. Inspectdrain plug threads for stretching or
other damage. Replace drain plug if damaged.
6. Install drain plug in crankcase.
7. Lower vehicle and fill crankcase with specified type and amount of engine oil described in this section.
8. Install oil fill cap.
9. Start engine and inspect for leaks.
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10. Stop engine and inspect oil level.
NOTE:
Care should be exercised when disposing used engine oil after it has been drained from a vehicle engine.
Refer to the WARNING at beginning of this section.
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MANIFOLD-INTAKE
DESCRIPTION
The intake manifold (2) is made of a composite mate-
rial and features 300 mm (11.811 in.) long runners
which maximizes low end torque. The intake manifold
uses single plane sealing which consist of six individ-
ual press in place port gaskets to prevent leaks. The
throttle body attaches directly to the intake manifold.
Eight studs and two bolts are used to fasten the intake
to the head.
DIAGNOSIS AND TESTING -INTAKE MANIFOLD LEAKS
An intake manifold air leak is characterized by lower than normal manifoldvacuum. Also, one or more cylinders may
not be functioning.
WARNING: USE EXTREME CAUTION WHEN THE ENGINE IS OPERATING. DO NOT STAND IN ADIRECT LINE
WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE PULLEYS, BELTS OR THE FAN. DO NOT WEAR
LOOSE CLOTHING.
1. Start the engine.
2. Spray a small stream of water (spray bottle) at the suspected leak area.
3. If engine RPM’S change, the area of the suspected leak has been found.
4. Repair as required.
REMOVAL
1. Disconnect negative cable from battery.
2. Remove resonator assembly and air inlet hose.
3. Disconnect throttle and speed control cables.
4. Disconnect electrical connectors for the following components: Referto FUEL SYSTEM for component locations.
Manifold Absolute Pressure (MAP) Sensor
Intake Air Temperature (IAT) Sensor
Throttle Position (TPS) Sensor
Coolant Temperature (CTS) Sensor
Idle Air Control (IAC) Motor