camshaft position sensor JEEP GRAND CHEROKEE 2003 WJ / 2.G Owner's Guide

INSPECTION
Inspect the following components:
²Sprockets for excessive tooth wear. Some tooth
markings are normal and not a cause for sprocket
replacement.
²Idler sprocket assembly bushing and shaft for
excessive wear.
²Idler sprocket assembly spline joint. The joint
should be tight with no backlash or axial movement.
²Chain guides and tensioner arms. Replace these
parts if grooving in plastic face is more than 1 mm
(0.039 in.) deep. If plastic face is severely grooved or
melted, the tensioner lube jet may be clogged. The
tensioner should be replaced.
²secondary chain tensioner piston and ratcheting
device. Inspect for evidence of heavy contact between
tensioner piston and tensioner arm. If this condition
exist the tensioner and tensioner arm should be
replaced.
²Primary chain tensioner plastic faces. Replace as
required (Fig. 127).
INSTALLATION
(1) Using a vise, lightly compress the secondary
chain tensioner piston until the piston step is flush
with the tensioner body. Using a pin or suitable tool,
release ratchet pawl by pulling pawl back against
spring force through access hole on side of tensioner.
While continuing to hold pawl back, Push ratchet
device to approximately 2 mm from the tensioner
Fig. 124 Camshaft Position SensorÐRemoval
1 - CRANKSHAFT POSITION SENSOR
2 - CYLINDER HEAD COVER
3 - CAMSHAFT POSITION SENSOR
4 - RIGHT SIDE CYLINDER BLOCK
Fig. 125 Camshaft RotationÐLeft Side
1 - CAMSHAFT SPROCKET AND CHAIN
2 - ADJUSTABLE PLIERS
3 - CAMSHAFT
Fig. 126 Camshaft RotationÐRight Side
1 - ADJUSTABLE PLIERS
2 - CAMSHAFT DOWEL
WJENGINE - 4.7L 9 - 149
TIMING BELT/CHAIN AND SPROCKETS (Continued)

FUEL INJECTION
DIAGNOSIS AND TESTING
VISUAL INSPECTION
A visual inspection for loose, disconnected or incor-
rectly routed wires, vacuum lines and hoses should
be made. This should be done before attempting to
diagnose or service the fuel injection system. A visual
check will help spot these faults and save unneces-
sary test and diagnostic time. A thorough visual
inspection will include the following checks:
(1) Verify three 32±way electrical connectors are
fully inserted into connector of Powertrain Control
Module (PCM) (Fig. 1).
(2) Inspect battery cable connections. Be sure they
are clean and tight.
(3) Inspect fuel pump relay and air conditioning
compressor clutch relay (if equipped). Inspect ASD
and oxygen sensor heater relay connections. Inspect
starter motor relay connections. Inspect relays for
signs of physical damage and corrosion. The relays
are located in the Power Distribution Center (PDC)
(Fig. 2). Refer to label on PDC cover for relay loca-
tion.
(4) Inspect ignition coil connections (Fig. 3)or (Fig.
4).
(5) Verify camshaft position sensor wire connector
is firmly connected (Fig. 5) or (Fig. 6).
(6) Verify crankshaft position sensor wire connec-
tor is firmly connected (Fig. 7) or (Fig. 8).
Fig. 1 Powertrain Control Module (PCM) Location
1 - PCM
2 - COOLANT TANK
Fig. 2 Power Distribution Center (PDC) Location
1 - POWER DISTRIBUTION CENTER (PDC)
2 - BATTERY
Fig. 3 Ignition Coil ConnectorÐ4.0L Engine
1 - REAR OF VALVE COVER
2 - COIL RAIL
3 - COIL CONNECTOR
4 - RELEASE LOCK
5 - SLIDE TAB
14 - 32 FUEL INJECTIONWJ

(7) Verify generator output wire (B+ wire) and
generator field connector are firmly connected to gen-
erator.
Fig. 4 Ignition Coil ConnectorÐ4.7L V-8 Engine
1 - IGNITION COIL
2 - COIL ELECTRICAL CONNECTOR
3 - COIL MOUNTING STUD/NUT
Fig. 5 Camshaft Position SensorÐ4.0L Engine
1 - OIL FILTER
2 - CAMSHAFT POSITION SENSOR
3 - CLAMP BOLT
4 - HOLD-DOWN CLAMP
5 - MOUNTING BOLTS (2)
6 - ELEC. CONNECTOR
Fig. 6 Camshaft Position SensorÐ4.7L V-8 Engine
1 - RIGHT CYLINDER HEAD
2 - CAMSHAFT POSITION SENSOR
3 - MOUNTING BOLT
4 - ELEC. CONNECTOR
Fig. 7 Crankshaft Position SensorÐ4.0L Engine
1 - SLOTTED HOLE
2 - CRANKSHAFT POSITION SENSOR
3 - WIRE SHIELD
4 - MOUNTING BOLT
5 - TRANSMISSION HOUSING
6 - PAPER SPACER
WJFUEL INJECTION 14 - 33
FUEL INJECTION (Continued)

(M)Malfunction Indicator Lamp (MIL) illuminated during engine operation if this DTC was recorded
(depending if required by CARB and/or EPA). MIL is displayed as an engine icon on instrument panel.
(G)Generator lamp illuminated
Generic Scan
Tool P-CodeDRB Scan Tool Display Brief Description of DTC
P0336 (M) Crankshaft Position (CKP) Sensor
SignalProblem with voltage signal from CKP.
P0340 (M) No Cam Signal At PCM No fuel sync
P0341 (M) Camshaft Position (CMP) Sensor
SignalProblem with voltage signal from CMP.
P0350 Ignition Coil Draws Too Much
CurrentA coil (1-5) is drawing too much current.
P0351 (M) Ignition Coil # 1 Primary Circuit Peak primary circuit current not achieved with maximum
dwell time.
P0352 (M) Ignition Coil # 2 Primary Circuit Peak primary circuit current not achieved with maximum
dwell time.
P0353 (M) Ignition Coil # 3 Primary Circuit Peak primary circuit current not achieved with maximum
dwell time.
P0354 (M) Ignition Coil # 4 Primary Circuit Peak primary circuit current not achieved with maximum
dwell time (High Impedance).
P0355 (M) Ignition Coil # 5 Primary Circuit Peak primary circuit current not achieved with maximum
dwell time (High Impedance).
P0356 (M) Ignition Coil # 6 Primary Circuit Peak primary circuit current not achieved with maximum
dwell time (high impedance).
P0357 (M) Ignition Coil # 7 Primary Circuit Peak primary circuit current not achieved with maximum
dwell time (high impedance).
P0358 (M) Ignition Coil # 8 Primary Circuit Peak primary circuit current not achieved with maximum
dwell time (high impedance).
P0370 Fuel Injection Pump Speed/Position
Sensor Sig LostProblem caused by internal fuel injection pump failure.
P0380 (M) Intake Air Heater Relay #1 Control
CircuitProblem detected in #1 air heater solenoid/relay circuit
(not heater element)
P0381 (M) Wait To Start Lamp Inoperative Problem detected in wait-to-start bulb circuit.
P0382 (M) Intake Air Heater Relay #2 Control
CircuitProblem detected in #2 air heater solenoid/relay circuit
(not heater element)
P0387 Crankshaft Position Sensor Supply
Voltage Too LowCKP sensor voltage input below the minimum acceptable
voltage.
P0388 Crankshaft Position Sensor Supply
Voltage Too HighCKP sensor voltage input above the maximum acceptable
voltage.
PO0400 Diesel EGR System Failure
P0401 EGR System Failure Required change in air/fuel ration not detected during
diagnostic test.
P0403 EGR Solenoid Circuit An open or shorted condition detected in the EGR
solenoid control circuit.
P0404 EGR Position Sensor Rationality EGR position sensor signal does not correlate to EGR
duty cycle.
P0405 EGR Position Sensor Volts Too Low EGR position sensor input below the acceptable voltage
range.
WJEMISSIONS CONTROL 25 - 7
EMISSIONS CONTROL (Continued)