WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
(1) From the face of the driver side inboard bezel,
align the headlamp leveling switch housing to the
mounting hole in the bezel (Fig. 36).
(2) Push the headlamp leveling switch into the
mounting hole until it is fully seated and the upper
latch and two lower latch features on the switch
housing are engaged on the back of the bezel.
(3) Position the switch and bezel unit to the
instrument panel.
(4) Reconnect the instrument panel wire harness
connector for the headlamp leveling switch to the
switch connector receptacle.
(5) Reinstall the driver side inboard bezel onto the
instrument panel. (Refer to 23 - BODY/INSTRU-
MENT PANEL/INSTRUMENT PANEL DRIVER
SIDE BEZEL - INSTALLATION).
(6) Reconnect the battery negative cable.
HEADLAMP LOW BEAM RELAY
DESCRIPTION
The headlamp low beam relay is located in the
Junction Block (JB) below the driver side outboard
end of the instrument panel in the passenger com-
partment of the vehicle. The headlamp low beam
relay is a conventional International Standards
Organization (ISO) micro relay (Fig. 37). Relays con-
forming to the ISO specifications have common phys-
ical dimensions, current capacities, terminal
patterns, and terminal functions. The relay is con-
tained within a small, rectangular, molded plastic
housing and is connected to all of the required inputs
and outputs by five integral male spade-type termi-
nals that extend from the bottom of the relay base.
The headlamp low beam relay cannot be adjusted
or repaired and, if faulty or damaged, the unit must
be replaced.
OPERATION
The headlamp low beam relay is an electromechan-
ical switch that uses a low current input from the
Body Control Module (BCM) to control a high current
output to the headlamp low beam filaments. The
movable common feed contact point is held against
the fixed normally closed contact point by spring
pressure. When the relay coil is energized, an electro-
magnetic field is produced by the coil windings. This
electromagnetic field draws the movable relay con-
tact point away from the fixed normally closed con-
tact point, and holds it against the fixed normally
open contact point. When the relay coil is de-ener-
gized, spring pressure returns the movable contact
point back against the fixed normally closed contact
point. A resistor is connected in parallel with the
relay coil in the relay, and helps to dissipate voltage
spikes and electromagnetic interference that can be
generated as the electromagnetic field of the relay
coil collapses.
The headlamp low beam relay terminals are con-
nected to the vehicle electrical system through a con-
nector receptacle in the Junction Block (JB). The
inputs and outputs of the headlamp low beam relay
include:
²Common Feed Terminal- The common feed
terminal (30) receives battery current at all times
from a fuse in the Power Distribution Center (PDC)
through a fused B(+) circuit.
²Coil Ground Terminal- The coil ground termi-
nal (85) receives battery current at all times from a
fuse in the PDC through a fused B(+) circuit.
Fig. 37 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
KJLAMPS8Ls-39
HEADLAMP LEVELING SWITCH (Continued)
8W-02 COMPONENT INDEX
Component Page
A/C Compressor Clutch Relay........... 8Wa-42
A/C Compressor Clutch................ 8Wa-42
A/C-Heater Control................... 8Wa-42
A/C High Pressure Switch.............. 8Wa-42
A/C Low Pressure Switch............... 8Wa-42
A/C Pressure Transducer............... 8Wa-42
Accelerator Pedal Position Sensor........ 8Wa-30
Airbag Control Module................. 8Wa-43
Ambient Temperature Sensor............ 8Wa-45
Antenna Module...................... 8Wa-47
Antenna............................ 8Wa-47
Ash Receiver Lamp................... 8Wa-44
Auto Shut Down Relay................. 8Wa-30
Back-Up Lamp Switch................. 8Wa-31
Battery Temperature Sensor......... 8Wa-20, 30
Battery............................. 8Wa-20
Blend Door Actuator................... 8Wa-42
Blower Motor Relay................... 8Wa-42
Blower Motor Resistor Block............ 8Wa-42
Blower Motor........................ 8Wa-42
Body Control Module.................. 8Wa-45
Boost Pressure Sensor................. 8Wa-30
Brake Lamp Switch................... 8Wa-33
Brake Pressure Switch................. 8Wa-35
Cabin Heater Relay................... 8Wa-42
Cabin Heater........................ 8Wa-42
Camshaft Position Sensor.............. 8Wa-30
Capacitor........................... 8Wa-30
Cargo Lamp......................... 8Wa-44
CD Changer......................... 8Wa-47
Center High Mounted Stop Lamp........ 8Wa-51
Cigar Lighter........................ 8Wa-41
Circuit Breakers...................... 8Wa-12
Clockspring................. 8Wa-33, 41, 43, 47
Clutch Interlock Switch................ 8Wa-21
Clutch Switch Override Relay........... 8Wa-21
Coil On Plugs........................ 8Wa-30
Coil Rail............................ 8Wa-30
Compass Mini-Trip Computer........... 8Wa-49
Controller Antilock Brake.............. 8Wa-35
Courtesy Lamps...................... 8Wa-44
Crankshaft Position Sensor............. 8Wa-30
Curtain Airbags...................... 8Wa-43
Cylinder Lock Switches................ 8Wa-61
Data Link Connector.................. 8Wa-18
Daytime Running Lamp Relay........... 8Wa-50
Defogger Relay....................... 8Wa-48
Diagnostic Junction Port............... 8Wa-18
Dome Lamp......................... 8Wa-44
Door Ajar Switches.................... 8Wa-45
Door Lock Motor/Ajar Switches.......... 8Wa-61
Door Lock Relay...................... 8Wa-61Component Page
Door Lock Switches................... 8Wa-61
Door Speakers....................... 8Wa-47
Driver Airbag Squib 1................. 8Wa-43
Driver Airbag Squib 2................. 8Wa-43
Driver Door Unlock Relay.............. 8Wa-61
Driver Seat Belt Switch................ 8Wa-40
Driver Seat Belt Tensioner.............. 8Wa-43
EGR Solenoid........................ 8Wa-30
Electric Brake Provision................ 8Wa-54
Engine Control Module................ 8Wa-30
Engine Coolant Level Sensor............ 8Wa-40
Engine Coolant Temperature Sensor...... 8Wa-30
Engine Oil Pressure Sensor............. 8Wa-30
EVAP/Purge Solenoid.................. 8Wa-30
Flip-Up Glass Release Motor............ 8Wa-61
Flip-Up Glass Release Switch........... 8Wa-61
Fog Lamps.......................... 8Wa-50
Front Fog Lamp Relay................. 8Wa-50
Front Wiper Motor.................... 8Wa-53
Fuel Heater Relay.................... 8Wa-30
Fuel Heater......................... 8Wa-30
Fuel Injectors........................ 8Wa-30
Fuel Pressure Sensor.................. 8Wa-30
Fuel Pressure Solenoid................. 8Wa-30
Fuel Pump Module.................... 8Wa-30
Fuel Pump Relay..................... 8Wa-30
Fuses........................... 8Wa-10, 12
Fusible Link......................... 8Wa-20
Grounds............................ 8Wa-15
Generator........................... 8Wa-20
Glow Plugs.......................... 8Wa-30
Hazard Switch/Combination Flasher...... 8Wa-52
Headlamp Leveling Switch.............. 8Wa-50
Headlamps.......................... 8Wa-50
Heated Seats........................ 8Wa-63
High Beam Relay..................... 8Wa-50
Horns.............................. 8Wa-41
Hood Ajar Switch..................... 8Wa-45
Idle Air Control Motor................. 8Wa-30
Ignition Switch....................... 8Wa-10
Impact Sensors....................... 8Wa-43
Input Speed Sensor................... 8Wa-31
Instrument Cluster................... 8Wa-40
Instrument Panel Speakers............. 8Wa-47
Intake Air Temperature Sensor.......... 8Wa-30
Intrusion Sensor..................... 8Wa-49
Junction Block....................... 8Wa-12
Knock Sensor........................ 8Wa-30
Leak Detection Pump.................. 8Wa-30
Leveling Motors...................... 8Wa-50
License Lamp........................ 8Wa-51
Line Pressure Sensor.................. 8Wa-31
KJ8W-02 COMPONENT INDEX8Wa-02-1
Component Page
C316 (Built-Up-Export).............. 8Wa-80-46
C316 (Built-Up-Export).............. 8Wa-80-46
C317 (Except Built-Up-Export)........ 8Wa-80-47
C317 (Except Built-Up-Export)........ 8Wa-80-47
Cabin Heater (Diesel)............... 8Wa-80-47
Camshaft Position Sensor (2.4L)....... 8Wa-80-47
Camshaft Position Sensor (3.7L)....... 8Wa-80-47
Camshaft Position Sensor (Diesel)...... 8Wa-80-48
Capacitor......................... 8Wa-80-48
Cargo Lamp (Except Base)........... 8Wa-80-48
CD Changer...................... 8Wa-80-48
Center High Mounted Stop Lamp...... 8Wa-80-49
Cigar Lighter..................... 8Wa-80-49
Clockspring C1.................... 8Wa-80-49
Clockspring C2.................... 8Wa-80-49
Clockspring C3.................... 8Wa-80-49
Clutch Interlock Switch (M/T)......... 8Wa-80-50
Coil On Plug No. 1 (3.7L)............ 8Wa-80-50
Coil On Plug No. 2 (3.7L)............ 8Wa-80-50
Coil On Plug No. 3 (3.7L)............ 8Wa-80-50
Coil On Plug No. 4 (3.7L)............ 8Wa-80-50
Coil On Plug No. 5 (3.7L)............ 8Wa-80-51
Coil On Plug No. 6 (3.7L)............ 8Wa-80-51
Coil Rail (2.4L).................... 8Wa-80-51
Compass Mini-Trip Computer
(Premium)...................... 8Wa-80-51
Controller Antilock Brake............ 8Wa-80-52
Crankshaft Position Sensor (2.4L)...... 8Wa-80-52
Crankshaft Position Sensor (3.7L)...... 8Wa-80-52
Crankshaft Position Sensor (Diesel).... 8Wa-80-53
Data Link Connector................ 8Wa-80-53
Diagnostic Junction Port............. 8Wa-80-53
Dome Lamp (Base)................. 8Wa-80-54
Driver Airbag Squib 1............... 8Wa-80-54
Driver Airbag Squib 2............... 8Wa-80-54
Driver Seat Belt Switch............. 8Wa-80-54
Driver Seat Belt Tensioner........... 8Wa-80-54
EGR Solenoid (Diesel)............... 8Wa-80-55
Engine Control Module C1........... 8Wa-80-55
Engine Control Module C2........... 8Wa-80-56
Engine Coolant Level Sensor (Diesel) . . . 8Wa-80-57
Engine Coolant Temp Sensor (Diesel) . . . 8Wa-80-57
Engine Coolant Temperature
Sensor (Gas).................... 8Wa-80-58
Engine Oil Pressure Sensor........... 8Wa-80-58
Evap/Purge Solenoid................ 8Wa-80-58
Flip-Up Glass Release Motor.......... 8Wa-80-58
Flip-Up Glass Release Switch......... 8Wa-80-58
Front Wiper Motor................. 8Wa-80-59
Fuel Heater (Diesel)................ 8Wa-80-59
Fuel Injector No. 1 (Diesel)........... 8Wa-80-59
Fuel Injector No. 1 (Gas)............. 8Wa-80-59
Fuel Injector No. 2 (Diesel)........... 8Wa-80-59
Fuel Injector No. 2 (Gas)............. 8Wa-80-60Component Page
Fuel Injector No. 3 (Diesel)........... 8Wa-80-60
Fuel Injector No. 3 (Gas)............. 8Wa-80-60
Fuel Injector No. 4 (Diesel)........... 8Wa-80-60
Fuel Injector No. 4 (Gas)............. 8Wa-80-60
Fuel Injector No. 5 (3.7L)............ 8Wa-80-61
Fuel Injector No. 6 (3.7L)............ 8Wa-80-61
Fuel Pressure Sensor (Diesel)......... 8Wa-80-61
Fuel Pressure Solenoid (Diesel)........ 8Wa-80-61
Fuel Pump Module................. 8Wa-80-61
G202............................ 8Wa-80-61
Generator........................ 8Wa-80-62
Glow Plug Assembly (Diesel).......... 8Wa-80-62
Hazard Switch/Combination Flasher.... 8Wa-80-62
Headlamp Leveling Switch
(Built-Up-Export)................ 8Wa-80-63
Heated Seat Module (Highline)........ 8Wa-80-63
High Note Horn.................... 8Wa-80-63
Hood Ajar Switch (Except Base)....... 8Wa-80-63
Idle Air Control Motor............... 8Wa-80-64
Ignition Switch.................... 8Wa-80-64
Input Speed Sensor (3.7L)............ 8Wa-80-64
Instrument Cluster................. 8Wa-80-64
Intake Air Temperature Sensor (Gas) . . . 8Wa-80-65
Intrusion Sensor (Built-Up-Export)..... 8Wa-80-65
Junction Block Body Control Module-JB . 8Wa-80-65
Junction Block C1.................. 8Wa-80-66
Junction Block C2.................. 8Wa-80-67
Junction Block C3.................. 8Wa-80-68
Knock Sensor (3.7L)................ 8Wa-80-69
Leak Detection Pump............... 8Wa-80-69
Left Courtesy Lamp................ 8Wa-80-69
Left Curtain Airbag................. 8Wa-80-69
Left Cylinder Lock Switch (Except Base) . 8Wa-80-69
Left Door Lock Switch (Except Base) . . . 8Wa-80-70
Left Fog Lamp..................... 8Wa-80-70
Left Front Door Ajar Switch (Base)..... 8Wa-80-70
Left Front Door Lock Motor/Ajar Switch
(Except Base)................... 8Wa-80-70
Left Front Door Speaker (Base)........ 8Wa-80-70
Left Front Door Speaker (Premium).... 8Wa-80-71
Left Front Impact Sensor............ 8Wa-80-71
Left Front Park/Turn Signal Lamp..... 8Wa-80-71
Left Front Power Window Motor
(Midline/Highline)................ 8Wa-80-71
Left Front Wheel Speed Sensor (ABS) . . . 8Wa-80-72
Left Headlamp (Built-Up-Export)...... 8Wa-80-72
Left Headlamp (Except Built-Up-Export) . 8Wa-80-72
Left Heated Seat Assembly (Highline) . . . 8Wa-80-72
Left Heated Seat Switch (Highline)..... 8Wa-80-72
Left Instrument Panel Speaker........ 8Wa-80-73
Left Leveling Motor (Built-Up-Export) . . 8Wa-80-73
Left Position Lamp (Built-Up-Export) . . . 8Wa-80-73
Left Power Mirror (Except Base)....... 8Wa-80-73
8Wa - 80 - 2 8W-80 CONNECTOR PIN-OUTSKJ
EGR SOLENOID (DIESEL)-2WAY
CAV CIRCUIT FUNCTION
1 A71 18DG/RD FUSED AUTO SHUT DOWN RELAY OUTPUT
2 K35 18GY/YL EGR SOLENOID CONTROL
ENGINE CONTROL MODULE C1 (DIESEL) - BLACK 81 WAY
CAV CIRCUIT FUNCTION
1 Z108 14BK/DG GROUND
2 Z108 14BK/DG GROUND
3 K20 18DG GENERATOR FIELD CONTROL
4 A142 14DG/OR AUTO SHUT DOWN RELAY OUTPUT
5 A142 14DG/OR AUTO SHUT DOWN RELAY OUTPUT
6- -
7 D25 20VT/YL PCI BUS
8 K944 20BK/LB CAMSHAFT POSITION SENSOR GROUND
9 K44 20TN/YL CAMSHAFT POSITION SENSOR SIGNAL
10 - -
11 K37 20DB/YL BOOST PRESSURE SENSOR SIGNAL
12 - -
13 K78 20GY FUEL PRESSURE SENSOR SIGNAL
14 - -
15 K81 20VT/TN ACCELERATOR PEDAL POSITION SENSOR SIGNAL
16 K80 20BK/VT FUEL PRESSURE SENSOR GROUND
17 - -
18 - -
19 F92 20YL/BR BATTERY SENSE (+)
20 Z109 20BK/DB BATTERY SENSE (-)
21 K4 20BK/LB SENSOR GROUND
22 F1 20DB FUSED IGNITION SWITCH OUTPUT (RUN-START)
23 K6 20VT/WT SENSOR REFERENCE VOLTAGE B
24 K3 20LB/BK CRANKSHAFT POSITION SENSOR SIGNAL 2
25 - -
26 - -
27 - -
28 - -
29 K77 20BR/WT TRANSFER CASE POSITION SENSOR INPUT
30 G60 20GY/YL ENGINE OIL PRESSURE SENSOR SIGNAL
31 G123 20DG/WT WATER IN FUEL SENSOR SIGNAL
32 K118 20PK/YL BATTERY TEMPERATURE SENSOR SIGNAL
33 - -
34 K255 20WT/DG ACCELERATOR PEDAL POSITION SENSOR GROUND
35 K852 20VT/WT ACCELERATOR PEDAL POSITION SENSOR 5 VOLT
SUPPLY
36 - -
37 - -
38 V37 20RD/LG SPEED CONTROL SWITCH SIGNAL
39 K226 20DB/WT FUEL LEVEL SENSOR SIGNAL
40 K2 20TN/BK ENGINE COOLANT TEMPERATURE SENSOR SIGNAL
41 K21 18BK/RD INTAKE AIR TEMPERATURE SENSOR SIGNAL
42 Y101 20BK/OR CRANKSHAFT POSITION SENSOR SHIELD
43 K24 20GY/BK CRANKSHAFT POSITION SENSOR SIGNAL 1
KJ8W-80 CONNECTOR PIN-OUTS8Wa-80-55
CONNECTOR NAME/NUMBER COLOR LOCATION FIG.
Coil On Plug No.5 (3.7L) BK Left Side of Engine Near
Fuel Injector No.51
Coil On Plug No.6 (3.7L) BK Right Side of Engine Near
Fuel Injector No.62
Coil Rail (2.4L) BK Right Side of Engine 11, 12
Combination Flasher WT Under Left Side of
Instrument PanelN/S
Compass Mini-Trip Computer BK At Overhead Console N/S
Controller Antilock Brake BK Left Side of Engine
Compartment30
Crankshaft Position Sensor (2.4L) BK Top of Engine N/S
Crankshaft Position Sensor (3.7L) BK Right Lower Side of Engine 4
Crankshaft Position Sensor (Diesel) BK Right Rear Side of Engine 17
Data Link Connector BK Under Center of Instrument
PanelN/S
Diagnostic Junction Port BK Under Center of Instrument
Panel49
Dome Lamp (Base) BK On Headliner N/S
Driver Airbag Squib 1 GY In Steering Wheel N/S
Driver Airbag Squib 2 BK In Steering Wheel N/S
Driver Seat Belt Switch LG At Drive Seat N/S
Driver Seat Belt Tensioner (LHD) YL Lower Left B-Pillar 35
Driver Seat Belt Tensioner (RHD) YL Lower Right B-Pillar 39
EGR Solenoid Right Rear Side of Engine
Compartment27
Engine Control Module C1 BK Left Rear Side of Engine
Compartment19
Engine Control Module C2 BK Left Rear Side of Engine
Compartment19
Engine Coolant Level Sensor (Diesel) LG Rear Side of Engine
Compartment18
Engine Coolant Temperature Sensor
(Diesel)BK Left Side of Engine 20
Engine Coolant Temperature Sensor
(Gas)BK Front Side of Engine 2
Engine Oil Pressure Sensor (2.4L) BK Top of Engine N/S
Engine Oil Pressure Sensor (3.7L) BK Left Front Side of Engine 3
Engine Oil Pressure Sensor (Diesel) BK Right Rear Side of Engine 17
Engine Starter Motor Right Front Side of Engine 20
Evap/Purge Solenoid BK At Solenoid N/S
Flip-Up Glass Release Motor BK In Tailgate 46
Flip-Up Glass Release Switch WT In Tailgate 46
Front Washer Pump BK Right Front Side of Engine
Compartment28
Front Wiper Motor (LHD) BK Left Side of Cowl 24
8Wa - 91 - 4 8W-91 CONNECTOR/GROUND/SPLICE LOCATIONKJ
CONNECTOR/GROUND/SPLICE LOCATION (Continued)
DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - MECHANICAL
CONDITION POSSIBLE CAUSES CORRECTIONS
NOISY VALVES 1. High or low oil level in
crankcase.1. (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
SPECIFICATIONS).
2. Thin or diluted oil. 2. Change oil and filter.
3. Low oil pressure. 3. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
4. Dirt in lash adjusters. 4. Clean or replace as necessary.
5. Worn rocker arms. 5. Replace as necessary.
7. Worn valve guides. 7. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE).
8. Excessive runout of valve seats
on valve faces.8. Service valves and valve seats.
(Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE).
ENGINE VIBRATION 1. Counter Balance Shaft not timed
properly1. Refer to Engine Timing in this
section
CONNECTING ROD NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
SPECIFICATIONS).
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Connecting rod journal
out-of-round.5. Service or replace crankshaft.
6. Misaligned connecting rods. 6. Replace bent connecting rods.
MAIN BEARING NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
SPECIFICATIONS).
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Excessive end play. 5. Check thrust washers for wear.
6. Crankshaft journal out-of round. 6. Service or replace crankshaft.
7. Loose flywheel or torque
converter.7. Tighten to correct torque
9 - 6 ENGINE - 3.7LKJ
ENGINE - 3.7L (Continued)
DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - LUBRICATION
CONDITION POSSIBLE CAUSES CORRECTION
OIL LEAKS 1. Gaskets and O-Rings. 1.
(a) Misaligned or damaged. (a) Replace as necessary.
(b) Loose fasteners, broken or
porous metal parts.(b) Tighten fasteners, Repair or
replace metal parts.
2. Crankshaft rear seal 2. Replace as necessary (Refer to 9
- ENGINE/ENGINE BLOCK/
CRANKSHAFT OIL SEAL - REAR -
REMOVAL).
3. Crankshaft seal flange.
Scratched, nicked or grooved.3. Polish or replace crankshaft.
4. Oil pan flange cracked. 4. Replace oil pan (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN -
REMOVAL).
5. Timing chain cover seal
damaged.5. Re-seal timing cover.
6. Scratched or damaged vibration
damper hub.6. Polish or replace damper.
OIL PRESSURE DROP 1. Low oil level. 1. Check and correct oil level.
2. Faulty oil pressure sending unit. 2. Replace sending unit (Refer to 9
- ENGINE/LUBRICATION/OIL
PRESSURE SENSOR/SWITCH -
REMOVAL).
3. Low oil pressure. 3. Check oil pump and bearing
clearance.
4. Clogged oil filter. 4. Replace oil filter (Refer to 9 -
ENGINE/LUBRICATION/OIL FILTER
- REMOVAL).
5. Worn oil pump. 5. Replace oil pump (Refer to 9 -
ENGINE/LUBRICATION/OIL PUMP
- REMOVAL).
6. Thin or diluted oil. 6. Change oil and filter.
7. Excessive bearing clearance. 7. Replace as necessary.
8. Oil pump relief valve stuck. 8. Replace oil pump (Refer to 9 -
ENGINE/LUBRICATION/OIL PUMP
- REMOVAL).
9. Oil pump suction tube loose,
damaged or clogged.9. Replace as necessary.
KJENGINE - 3.7L 9 - 7
ENGINE - 3.7L (Continued)
CONDITION POSSIBLE CAUSES CORRECTION
OIL PUMPING AT RINGS; SPARK
PLUGS FOULING1. Worn or damaged rings. 1. Hone cylinder bores and replace
rings.
2. Carbon in oil ring slots. 2. Replace rings (Refer to 9 -
ENGINE/ENGINE BLOCK/PISTON
RINGS - STANDARD
PROCEDURE).
3. Incorrect ring size installed. 3. Replace rings (Refer to 9 -
ENGINE/ENGINE BLOCK/PISTON
RINGS - STANDARD
PROCEDURE).
4. Worn valve guides. 4. Ream guides and replace valves
(Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE).
5. Leaking valve guide seals. 5. Replace valve guide seals.
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE
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) Clean the spark plug recesses with compressed
air.
(2) Remove the spark plugs.
(3) Secure the throttle in the wide-open position.
(4) Disable the fuel system (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY - DESCRIPTION).
(5) Remove the ASD relay (Refer to 8 - ELECTRI-
CAL/IGNITION CONTROL/AUTO SHUT DOWN
RELAY - REMOVAL).
(6) Insert a compression pressure gauge and rotate
the engine with the engine starter motor for three
revolutions.
(7) Record the compression pressure on the 3rd
revolution. Continue the test for the remaining cylin-
ders.
(8) (Refer to 9 - ENGINE - SPECIFICATIONS) for
the correct engine compression pressures.
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE
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.
(1) Check the coolant level and fill as required. DO
NOT install the radiator cap.
(2) Start and operate the engine until it attains
normal operating temperature, then turn the engine
OFF.
(3) Remove the spark plugs.
(4) Remove the oil filler cap.
(5) Remove the air cleaner.
(6) Calibrate the tester according to the manufac-
turer's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379
kPa (200 psi) maximum and 552 kPa (80 psi) recom-
mended.
(7) Perform the test procedures on each cylinder
according to the tester manufacturer's instructions.
Set piston of cylinder to be tested at TDC compres-
sion,While testing, listen for pressurized air escaping
through the throttle body, tailpipe and oil filler cap
opening. Check for bubbles in the radiator coolant.
All gauge pressure indications should be equal,
with no more than 25% leakage.
FOR EXAMPLE:At 552 kPa (80 psi) input pres-
sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder.
Refer to CYLINDER COMBUSTION PRESSURE
LEAKAGE DIAGNOSIS CHART .
9 - 8 ENGINE - 3.7LKJ
ENGINE - 3.7L (Continued)