Page 1345 of 1938

(22) Check the accessory drive belt tension.
(23) Check the 40-way electrical connectors at the
Powertrain Control Module (PCM) (Fig. 59) for dam-
age or spread terminals. Verify that the connectors
are fully inserted into the PCM sockets. Ensure the
wires are not stretched or pulled out of the connector.
(24) Inspect fuses in the Power Distribution Cen-
ter (PDC). Verify all fuses and relays are fully
inserted into the PDC (Fig. 60). A label affixed to the
underside of the PDC cover identifies the relays and
fuses in the PDC.(25) Inspect battery cable connections for corro-
sion.
(26) Check the power brake booster hose connec-
tion (without anti-lock brake systems) (Fig. 61).
(27) Inspect the speed control vacuum connection.
(28) Inspect hose and wiring connections at fuel
pump module. Check that wiring connector is making
contact with terminals on pump.
Fig. 56 Map Sensor
Fig. 57 Upstream Heated Oxygen Sensor
Fig. 58 Downstream Heated Oxygen Sensor
Fig. 59 Powertrain Control Module (PCM)
Connectors
NSFUEL SYSTEM 14 - 51
DIAGNOSIS AND TESTING (Continued)
Page 1346 of 1938
VISUAL INSPECTIONÐ3.0L ENGINE
A visual inspection for loose, disconnected, or mis-
routed wires and hoses should be made before
attempting to diagnose or service the fuel injection
system. A visual check helps save unnecessary test
and diagnostic time. A thorough visual inspection will
include the following checks:(1) Check for correct spark plug cable routing.
Ensure that the cables are completely connected to
the spark plugs and distributor.
(2) Check ignition coil electrical connections (Fig.
62).
(3) Verify that the electrical connector is attached
to the Proportional Purge Solenoid (Fig. 63).
(4) Verify that vacuum connection at the duty cycle
Proportional Purge Solenoid valve is secure and not
leaking.
Fig. 60 Power Distribution Center (PDC)
Fig. 61 Power Brake Booster Hose
Fig. 62 Ignition Coil Electrical Connection
Fig. 63 Proportional Purge Solenoid Valve
14 - 52 FUEL SYSTEMNS
DIAGNOSIS AND TESTING (Continued)
Page 1347 of 1938

(5) Verify that the electrical connector is attached
to the MAP sensor (Fig. 64).
(6) Check generator wiring connections. Ensure
the accessory drive belt has proper tension.
(7) Verify that hoses are securely attached to the
evaporative canister (Fig. 65).
(8) Verify the engine ground strap is attached at
the engine and dash panel (Fig. 66).
(9) Ensure the heated oxygen sensor connector is
connected to the harness connector.
(10) Verify the distributor connector is connected
to the harness connector (Fig. 67).
(11) Verify the coolant temperature sensor connec-
tor is connected to the harness connector (Fig. 68).(12) Check vacuum hose connection at fuel pres-
sure regulator and intake plenum connector (Fig. 68).
Fig. 64 Map Sensor Electrical and Vacuum
Connections
Fig. 65 Evaporative Canister
Fig. 66 Engine Ground Strap
Fig. 67 Distributor Connector
Fig. 68 Coolant Temperature Sensor Electrical
Connections and Vacuum Hose Connections at the
Air Intake Plenum
NSFUEL SYSTEM 14 - 53
DIAGNOSIS AND TESTING (Continued)
Page 1348 of 1938

(13) Ensure the harness connector is securely
attached to each fuel injector.
(14) Check the oil pressure sending unit electrical
connection (Fig. 69).
(15) Check hose connections at throttle body.
(16) Check throttle body electrical connections
(Fig. 70).
(17) Check PCV hose connections (Fig. 71).
(18) Check EGR system vacuum hose connections
(Fig. 72).
(19) Check EGR tube to intake plenum connec-
tions.
(20) Check power brake booster vacuum connec-
tions.
(21) Check engine harness to main harness electri-
cal connections.
(22) Check all electronic automatic transaxle elec-
trical connections (Fig. 73).(23) Inspect the Powertrain Control Module (PCM)
40-way electrical connectors for damage or spread
Fig. 69 Oil Pressure Sending Unit Electrical
Connection
Fig. 70 Throttle Body Electrical and Vacuum Hose
Connections
Fig. 71 Positive Crankcase Ventilation (PCV) System
Fig. 72 EGR System
Fig. 73 Electronic Automatic Transaxle Electrical
Connections
14 - 54 FUEL SYSTEMNS
DIAGNOSIS AND TESTING (Continued)
Page 1349 of 1938

terminals. Verify the connectors are fully inserted
into the socket of the PCM (Fig. 74). Ensure that
wires are not stretched or pulled out of the connector.
(24) Inspect fuses in the Power Distribution Cen-
ter (PDC). Verify all fuses and relays are fully
inserted into the PDC (Fig. 74). A label affixed to the
underside of the PDC cover identifies the relays and
fuses in the PDC.
(25) Check Battery Cable Connections.
(26) Check hose and wiring connections at fuel
pump module. Check that wiring connector is making
contact with terminals on pump.
VISUAL INSPECTIONÐ3.3/3.8L ENGINES
A visual inspection for loose, disconnected, or mis-
routed wires and hoses should be made before
attempting to diagnose or service the fuel injection
system. A visual check helps save unnecessary test
and diagnostic time. A thorough visual inspection will
include the following checks:
(1) Check ignition cable routing from the coil pack
to the spark plugs. Verify the cable are routed in the
correct order and are fully seated to the coil and
spark plug.(2) Check direct ignition system (DIS) coil electri-
cal connection for damage and a complete connection
to the coil pack (Fig. 75).
(3) Verify the camshaft position sensor electrical
connector is connected to the harness and not dam-
aged (Fig. 76).
(4) Ensure the engine temperature sensor electri-
cal connector is connected to the sensor and not dam-
aged (Fig. 77).
(5) Verify the quick connect fuel fitting is fully
inserted on the fuel supply tube.
(6) Check the oil pressure sending unit electrical
connection (Fig. 78).
Fig. 74 Powertrain Control Module (PCM)
Fig. 75 Ignition Coil Pack Electrical Connection
Fig. 76 Camshaft Position Sensor
NSFUEL SYSTEM 14 - 55
DIAGNOSIS AND TESTING (Continued)
Page 1350 of 1938
(7) Verify the electrical connector at the knock sen-
sor is fully seated and not damaged (Fig. 78).
(8) Verify the electrical connector is attached to
the Proportional purge solenoid (Fig. 79) and not
damaged.
(9) Verify the vacuum connection at the Propor-
tional purge solenoid is secure and not leaking (Fig.
79).(10) Verify the hoses are securely attached to the
EVAP canister (Fig. 80).
(11) Ensure the harness connectors for the fuel
injectors are attached to the correct injector and not
damaged.
(12) Verify the fuel injector harness and engine
wiring harness connectors are fully inserted into the
main wiring harness.
Fig. 77 Engine Coolant Temperature Sensor
Fig. 78 Knock Sensor and Oil Pressure Sending
Unit Electrical Connection
Fig. 79 Proportional Purge Solenoid
Fig. 80 Evaporative Canister
14 - 56 FUEL SYSTEMNS
DIAGNOSIS AND TESTING (Continued)
Page 1351 of 1938
(13) Check the vacuum connections at the throttle
body and intake plenum (Fig. 81).
(14) Ensure the idle air control motor and TPS
electrical connectors are fully seated and not dam-
aged (Fig. 82).
(15) Inspect the park/neutral switch wiring connec-
tion for damage. Ensure the automatic transaxle
electrical connections are not damaged (Fig. 83).(16) Inspect the PCV system connections for dam-
age (Fig. 84).
(17) Inspect the crankshaft position sensor electri-
cal connector for damage (Fig. 85).
(18) Verify the Manifold Absolute Pressure (MAP)
sensor electrical connector is attached to the sensor
and not damaged (Fig. 86).
Fig. 81 Throttle Body Vacuum Connections
Fig. 82 Throttle Body Electrical Connections
Fig. 83 Automatic Transaxle Electrical Connections
Fig. 84 PCV Valve and Fresh Air Hose
NSFUEL SYSTEM 14 - 57
DIAGNOSIS AND TESTING (Continued)
Page 1352 of 1938
(19) Check the heated oxygen sensor electrical con-
nectors for damage (Fig. 87) and (Fig. 88).(20) Verify the engine ground strap is attached at
the engine and dash panel. Inspect the strap for cor-
rosion or damage.
(21) Inspect the generator wiring connections for
damage.
(22) Check the accessory drive belt tension.
(23) Check the 40-way electrical connectors at the
Powertrain Control Module (PCM) (Fig. 89) for dam-
age or spread terminals. Verify that the connectors
are fully inserted into the PCM sockets. Ensure the
wires are not stretched or pulled out of the connector.
(24) Inspect fuses in the Power Distribution Cen-
ter (PDC). Verify all fuses and relays are fully
Fig. 85 Crankshaft Position Sensor
Fig. 86 MAP Sensor
Fig. 87 Upstream Heated Oxygen Sensor
Fig. 88 Downstream Heated Oxygen Sensor
Fig. 89 Powertrain Control Module (PCM)
Connectors
14 - 58 FUEL SYSTEMNS
DIAGNOSIS AND TESTING (Continued)