clutch DODGE NEON 2000 Service Manual PDF

Connector
Name/NumberColor Location Fig.
C204 RD Left Side of
Instrument
Panel6, 8, 9
C205 GY Left Side of
Instrument
Panel6, 8,
14
C301 RD Right C-Pillar 11
C302 BK Inner Left
Rear Quarter
Panel11
C303 BL/BK Left B-Pillar at
Rear Door10, 16
C304 BL/BK Right B-Pillar
at Rear Door12, 16
C305 NAT Left Side of
Instrument
Panel6, 8,
10
C306 BK Front Center
of Headliner9
Camshaft
Position
SensorBK Rear of
EngineN/S
Cargo Lamp BK Under Parcel
Shelf11
Center High
Mounted Stop
LampBK Rear of Lamp 17
Center Stack
LampBK Center of
Instrument
Panel7
Cigar
Lighter/Power
OutletRD Center of
Instrument
Panel7
Clockspring GN Rear of
Steering
Wheel6
Clutch
Interlock
Switch (MTX)BK Top of Clutch
Pedal2
Controller
Anti-Lock
BrakeBK Near Left
Strut Tower2
Crankshaft
Position
SensorBK Right Front of
EngineN/S
Data Link
ConnectorBK At Left Kick
Panel Area2Connector
Name/NumberColor Location Fig.
Decklid
SolenoidBK On Decklid 17
Dome Lamp
(Except
Built-Up-
Export)BK At Lamp N/S
Dome
Lamp/Intrusion
Sensor
(Built-Up-
Export)NAT At Lamp N/S
Driver Cylinder
Lock SwitchBK At Drivers
Door14
Driver Door
Lock MotorBK At Drivers
Door14
Driver Door
Lock SwitchBK At Drivers
Door14
Driver Power
MirrorGY At Drivers
Door14
Driver Power
Window MotorBK At Drivers
Door14
Driver Power
Window
Switch - C1BK At Drivers
Door14
Driver Power
Window
Switch - C2GY At Drivers
Door14
Engine
Coolant
Temperature
SensorBK Right Front of
EngineN/S
Engine Oil
Pressure
SwitchGN Right Rear of
Engine5
Fuel Injector
NO.1BK At Injector 4
Fuel Injector
NO. 2BK At Injector 4
Fuel Injector
NO. 3BK At injector 4
Fuel Injector
NO. 4BK At Injector 4
Fuel Pump
ModuleLT GY At Fuel Tank N/S
G101 Left Front of
Engine
CompartmentN/S
8W - 90 - 2 8W - 90 CONNECTOR/GROUND LOCATIONSPL
DESCRIPTION AND OPERATION (Continued)

Connector
Name/NumberColor Location Fig.
Sunroof
Control
ModuleAt Sunroof N/S
Sunroof Motor At Sunroof N/S
Sunroof
SwitchBK At Switch N/S
Sunroof Vent
SwitchAt Switch N/S
Throttle
Position
SensorBK On Throttle
Body2
Torque
Converter
Clutch
Solenoid
(ATX)BK On
Transmission2
Traction
Control SwitchWT Center of
Instrument
Panel7Connector
Name/NumberColor Location Fig.
Trunk Key
Cylinder
SwitchGY On Decklid 17
Underhood
LampBK At Lamp N/S
Vehicle Speed
Control ServoBK At Right Front
Strut Tower1, 3
Vehicle Speed
SensorBK On
Transmission5
Windshield
Washer PumpRD At Right Front
Wheel
Opening1
Wipe/Wash
SwitchGY Center of
Instrument
Panel6
Wiper Motor BK Left Side of
Engine
CompartmentN/S
8W - 90 - 6 8W - 90 CONNECTOR/GROUND LOCATIONSPL
DESCRIPTION AND OPERATION (Continued)

CONNECTOR/GROUND LOCATIONS (RHD)
For items not shown in this section a N/S is placed
in the Fig. column.
Connector
Name/NumberColor Location Fig.
A/C
Compressor
ClutchBK Right Front of
Engine
Compartment20
A/C Cycling
SwitchBK Left Side of
Instrument
PanelN/S
A/C-Heater
Blower MotorBK Left Side of
Instrument
PanelN/S
A/C-Heater
ControlGY Center of
Instrument
Panel24
A/C High
Pressure
SwitchBK Front Center
of Engine
Compartment18, 20
A/C Low
Pressure
SwitchBK Left Rear of
Engine
CompartmentN/S
Airbag Control
ModuleYL Near PRNDL
Lamp T/O25
Back-Up Lamp
Switch (MTX)GY Left Front of
Engine
Compartment19
Blower Motor
Resistor BlockBK T/O Near
Grommet and
C20223
Brake Lamp
SwitchGY Top of Brake
Pedal23
Brake Shift
Interlock
SolenoidWT Right Side of
Instrument
PanelN/S
Brake Warning
Indicator
SwitchBK Rear of
Engine
CompartmentN/S
C101 BK Left Front of
Engine
Compartment19, 21
C102 LT GY Left Front of
Engine
Compartment19, 21
C103 BK Right Side of
Instrument
Panel23, 25,
26Connector
Name/NumberColor Location Fig.
C104 GY Right Side of
Instrument
Panel23, 25,
26
C105 BK Right Kick
Panel23, 29
C106 BK Left Rear of
Engine
Compartment19
C107 BK Near Left
Front Strut
Tower19
C108 BK Left Front of
Engine
Compartment19
C109 BK Right Front
Inner Fender18
C110 BK Left
Headlamp
Opening19
C111 BK Right
Headlamp
Opening20
C201 GY Left Side of
Instrument
Panel25, 33
C202 LT GN Left Side of
Instrument
Panel23, 24,
25
C203 LT GY Left Side of
Instrument
Panel24, 25
C204 RD Left Side of
Instrument
Panel24, 25,
27
C205 GY Right Side of
Instrument
Panel25, 26,
34
C301 RD Left C-Pillar 30
C302 BK Inner Left
Rear Quarter
Panel30
PL8W - 90 CONNECTOR/GROUND LOCATIONS 8W - 90 - 21
DESCRIPTION AND OPERATION (Continued)

Connector
Name/NumberColor Location Fig.
C303 BL/BK Left B-Pillar at
Left Rear
Door28, 35
C304 BL/BK Right B-Pillar
at Right Rear
Door29, 31,
35
C305 NAT Right Side of
Instrument
Panel25, 26,
29
C306 BK Front Center
of Headliner27
Camshaft
Position
SensorBK Rear of
EngineN/S
Cargo Lamp BK Under Parcel
Shelf30
Center High
Mounted Stop
LampBK Rear of Lamp 36
Center Stack
LampBK Center of
Instrument
Panel24
Cigar
Lighter/Power
OutletRD Center of
Instrument
Panel24
Clockspring GN Rear of
Steering
Wheel25
Clutch
Interlock
Switch (MTX)BK Top of Clutch
Pedal23
Controller
Anti-Lock
BrakeBK Near Left
Strut Tower19
Crankshaft
Position
SensorBK Right Front of
EngineN/S
Data Link
ConnectorBK Right Front
Kick Panel23
Decklid
SolenoidBK On Decklid 36
Dome
Lamp/Intrusion
SensorNAT At Lamp N/S
Driver Cylinder
Lock SwitchBK At Drivers
Door34
Driver Door
Lock MotorBK At Drivers
Door34Connector
Name/NumberColor Location Fig.
Driver Door
Lock SwitchBK At Drivers
Door34
Driver Power
MirrorBL At Drivers
Door34
Driver Power
Window MotorBK At Drivers
Door34
Driver Power
Window
Switch - C1BK At Drivers
Door34
Driver Power
Window
Switch - C2GY At Drivers
Door34
Engine
Coolant
Temperature
SensorBK Right Side of
EngineN/S
Engine Oil
Pressure
SwitchGN Right Rear of
Engine22
Fuel Injector
NO. 1BK At Injector 21
Fuel Injector
NO. 2BK At Injector 21
Fuel Injector
NO. 3BK At injector 21
Fuel Injector
NO. 4BK At Injector 21
Fuel Pump
ModuleLT GY At Fuel Tank N/S
G101 Left Front of
Engine
CompartmentN/S
G102 Left Front of
Engine
CompartmentN/S
G103 Right Front of
Engine
Compartment20
G104 Near Engine
Starter MotorN/S
G105 Near Negative
Battery
TerminalN/S
G201 Lower Center
of Instrument
Panel24, 26
8W - 90 - 22 8W - 90 CONNECTOR/GROUND LOCATIONSPL
DESCRIPTION AND OPERATION (Continued)

Connector
Name/NumberColor Location Fig.
Right Tail/Stop
LampBK At Lamp 31
Seat Belt
SwitchBK Under Drivers
SeatN/S
Sentry Key
Immobilizer
ModuleBK Right Side of
Instrument
Panel25
Siren Left Front of
Vehicle18
Sunroof
Control
ModuleAt Sunroof N/S
Sunroof Motor At Sunroof N/S
Sunroof
SwitchBK At Switch N/S
Sunroof Vent
SwitchAt Switch N/S
Throttle
Position
SensorBK On Throttle
Body19
Torque
Converter
Clutch
Solenoid
(ATX)BK On
Transmission19Connector
Name/NumberColor Location Fig.
Traction
Control SwitchWT Center of
Instrument
Panel24
Trunk Key
Cylinder
SwitchGY On Decklid 36
Underhood
LampBK At Lamp N/S
Vehicle Speed
Control ServoBK At Left Front
Strut Tower19
Vehicle Speed
SensorBK On
Transmission22
Windshield
Washer PumpRD At Right Front
Wheel
Opening18
Wipe/Wash
SwitchGY Center of
Instrument
Panel25
Wiper Motor BK Right Side of
Engine
Compartment23
PL8W - 90 CONNECTOR/GROUND LOCATIONS 8W - 90 - 25
DESCRIPTION AND OPERATION (Continued)

make sure the dye is thoroughly mixed as indicated
with a bright yellow color under a black light.
(3) Using a black light, inspect the entire engine
for fluorescent dye, particularly at the suspected area
of oil leak. If the oil leak is found and identified,
repair per service manual instructions.
(4) If dye is not observed, drive the vehicle at var-
ious speeds for approximately 24 km (15 miles), and
repeat inspection.
(5)If the oil leak source is not positively
identified at this time, proceed with the air leak
detection test method as follows:
²Disconnect the fresh air hose (makeup air) at
the cylinder head cover and plug or cap the nipple on
the cover.
²Remove the PCV valve hose from the cylinder
head cover. Cap or plug the PCV valve nipple on the
cover.
²Attach an air hose with pressure gauge and reg-
ulator to the dipstick tube.
CAUTION: Do not subject the engine assembly to
more than 20.6 kpa (3 PSI) of test pressure.
²Gradually apply air pressure from 1 psi to 2.5
psi maximum while applying soapy water at the sus-
pected source. Adjust the regulator to the suitable
test pressure that provides the best bubbles which
will pinpoint the leak source. If the oil leak is
detected and identified, repair per service manual
procedures.
²If the leakage occurs at the crankshaft rear oil
seal area, refer to the section, Inspection for Rear
Seal Area Leak.
(6) If no leaks are detected, turn off the air supply.
Remove the air hose, all plugs, and caps. Install the
PCV valve and CCV hose. Proceed to next step.
(7) Clean the oil off the suspect oil leak area using
a suitable solvent. Drive the vehicle at various
speeds approximately 24 km (15 miles). Inspect the
engine for signs of an oil leak by using a black light.
INSPECTION FOR REAR SEAL AREA LEAKS
Since it is sometimes difficult to determine the
source of an oil leak in the rear seal area of theengine, a more involved inspection is necessary. The
following steps should be followed to help pinpoint
the source of the leak.
If the leakage occurs at the crankshaft rear oil seal
area:
(1) Disconnect the battery.
(2) Raise the vehicle.
(3) Remove torque converter or clutch housing
cover and inspect rear of block for evidence of oil.
Use a black light to check for the oil leak. If a leak is
present in this area remove transmission for further
inspection.
(a) Circular spray pattern generally indicates
seal leakage or crankshaft damage.
(b) Where leakage tends to run straight down,
possible causes are a porous block, oil galley cup
plug, bedplate to cylinder block mating surfaces
and seal bore. See proper repair procedures for
these items.
(4) If no leaks are detected, pressurized the crank-
case as previously described.
CAUTION: Do not exceed 20.6 kPa (3 psi).
(5) If the leak is not detected, very slowly turn the
crankshaft and watch for leakage. If a leak is
detected between the crankshaft and seal while
slowly turning the crankshaft, it is possible the
crankshaft seal surface is damaged. The seal area on
the crankshaft could have minor nicks or scratches
that can be polished out with emery cloth.
CAUTION: Use extreme caution when crankshaft
polishing is necessary to remove minor nicks and
scratches. The crankshaft seal flange is especially
machined to complement the function of the rear oil
seal.
(6) For bubbles that remain steady with shaft
rotation, no further inspection can be done until dis-
assembled.
(7) After the oil leak root cause and appropriate
corrective action have been identified, refer to Crank-
shaft Oil SealÐRear for proper replacement proce-
dures.
9 - 10 ENGINEPL
DIAGNOSIS AND TESTING (Continued)

(4) Discharge air conditioning system, if equipped.
Refer to Group 24, Heating and Air Conditioning for
procedure.
(5) Disconnect the following: air intake duct at
intake manifold, throttle cables, electrical connectors
from throttle body and air cleaner housing.
(6) Remove air cleaner housing assembly.
(7) Remove upper radiator hose and fan module.
Refer to Group 7, Cooling System for procedure.
(8) Remove lower radiator hose.
(9) Disconnect automatic transmission cooler lines
and plug, if equipped.
(10) Disconnect shift linkage, electrical connectors,
and clutch cable, if equipped with manual transaxle.
(11) Disconnect engine wiring harness.
(12) Disconnect positive cable from Power Distri-
bution Center (PDC) and ground wire from vehicle
body.
(13) Disconnect ground wire from the vehicle body-
to-engine at the right side strut tower.
(14) Disconnect heater hoses.
(15) Disconnect vacuum hose from brake booster.
(16) Disconnect coolant reserve/recovery hose.
(17) Remove accessory drive belts. Refer to Group
7, Cooling System for procedure.
(18) Remove power steering pump and reservoir
and set them aside.
(19) Hoist vehicle and remove right inner splash
shield.
(20) Drain engine oil.
(21) Remove front wheels.
(22) Remove axle shafts. Refer to Group 3, Differ-
ential and Driveline for procedure.
(23) Disconnect exhaust system from manifold.
(24) Disconnect the downstream oxygen sensor
connector.
(25) Remove lower engine torque strut.
(26) Remove structural collar. Refer to procedure
in this section.
(27) Lower vehicle and remove A/C compressor.
(28) Raise vehicle enough to allow engine dolly
and cradle, Special Tools 6135 and 6710 to be
installed under vehicle.
(29) Loosen engine support posts to allow move-
ment for positioning onto engine locating holes and
flange on the engine bedplate. Lower vehicle and
position cradle until the engine is resting on support
posts (Fig. 26). Tighten mounts to cradle frame. This
will keep support posts from moving when removing
or installing engine and transmission.
(30) Install safety straps around the engine to cra-
dle (Fig. 26). Tighten straps and lock them into posi-
tion.
WARNING: Safety straps MUST be used.(31) Raise vehicle enough to see if straps are tight
enough to hold cradle assembly to engine.
(32) Lower vehicle so weight of the engine and
transmission ONLY is on the cradle assembly.
(33) Remove the upper engine torque strut.
(34) Remove right and left engine and transaxle
mount through bolts (Fig. 24) and (Fig. 25).
(35) Raise vehicle slowly until body is approxi-
mately 15 cm (6 in.) above normal engine mounting
locations.
(36) Remove generator, lower bracket, and upper
mounting bolt.
(37) Continue raising vehicle slowly until engine/
transaxle assembly clears engine compartment. It
may be necessary to move the engine/transmission
assembly with the cradle to allow for removal around
body flanges.
INSTALLATION
(1) Position engine and transmission assembly
under vehicle and slowly lower the vehicle over the
engine/transaxle assembly until vehicle is within 15
cm (6 in.) of engine mounting locations.
(2) Install generator, lower bracket, and adjusting
bolt.
(3) Continue lowering vehicle until engine/tran-
saxle aligns to mounting locations. Install mounting
bolts at the right and left engine/transaxle mounts
(Fig. 24) and (Fig. 25). Tighten bolts to 118 N´m (87
ft. lbs.).
(4) Install upper engine torque strut. Refer to pro-
cedure in this section.
(5) Remove safety straps from engine/transaxle
assembly. Slowly raise vehicle enough to remove the
engine dolly and cradle.
(6) Install axle shafts. Refer to Group 3, Differen-
tial and Driveline for procedure.
(7) Install structural collar. Refer to procedure in
this section tightening sequence.
Fig. 24 Right Mount Through Bolt
1 ± BOLT
2 ± RIGHT ENGINE MOUNT
3 ± ENGINE MOUNT BRACKET
9 - 26 2.0L SOHC ENGINEPL
REMOVAL AND INSTALLATION (Continued)

(8) Install lower engine torque strut. Refer to pro-
cedure in this section.
(9) Connect exhaust system to manifold. Refer to
Group 11, Exhaust System for procedure and torque
specifications.
(10) Connect the downstream oxygen sensor.
(11) Install A/C compressor and hoses. Refer to
Group 24, Heater and Air Conditioning for procedure.
(12) Install accessory drive belts. Refer to Group 7,
Cooling System Accessory Drive Section for belt ten-
sion adjustment.
(13) Install inner splash shield.
(14) Install wheels and lower vehicle.
(15) Install power steering pump and reservoir.
Refer to Group 7, Cooling System Accessory Drive
Section for belt tension adjustment.
(16)Manual Transmission:Connect clutch cable,
reverse light electrical connector and shift linkages.
Refer to Group 6, Clutch.
(17)Automatic Transmission:Connect shifter,
kickdown linkage and cooler lines. Refer to Group 21,
Transaxle for procedures.
(18) Connect fuel line and heater hoses.
(19)
Install all ground straps. Connect engine wiring
harness. Refer to Group 8, Electrical for procedure.
(20) Install lower radiator hose, fan module, and
upper radiator hose. Refer to Group 7, Cooling Sys-
tem for procedures
(21) Fill cooling system. Refer to Group 7, Cooling
System for filling procedure.
(22) Install battery tray and battery.
(23) Install air cleaner housing assembly and con-
nect intake duct to intake manifold.(24) Connect all throttle body electrical connectors
and linkage.
(25) Install oil filter. Fill engine crankcase with
proper oil to correct level.
(26) Perform camshaft and crankshaft timing
relearn procedure as follows:
²Connect the DRB scan tool to the data link
(diagnostic) connector. This connector is located in
the passenger compartment; at the lower edge of
instrument panel; near the steering column.
²Turn the ignition switch on and access the ªmis-
cellaneousº screen.
²Select ªre-learn cam/crankº option and follow
directions on DRB screen.
Fig. 25 Left Mount Through Bolt
1 ± MOUNT BRACKET
2 ± BOLT
3 ± MOUNT
Fig. 26 Positioning Engine Cradle Support Post
1 ± SAFETY STRAPS
2 ± PLACE REAR POSTS INTO LOCATING HOLES
3 ± SPECIAL TOOL 6848
4 ± SPECIAL TOOL 6710
5 ± SPECIAL TOOL 6135
6 ± SAFETY STRAPS
7 ± PLACE FRONT POST UNDER BLOCK FLANGE
PL2.0L SOHC ENGINE 9 - 27
REMOVAL AND INSTALLATION (Continued)

FUEL INJECTION SYSTEM
TABLE OF CONTENTS
page page
DESCRIPTION AND OPERATION
INJECTION SYSTEM......................22
MODES OF OPERATION...................22
SYSTEM DIAGNOSIS......................24
POWER DISTRIBUTION CENTER............24
POWERTRAIN CONTROL MODULE...........24
PCM GROUND...........................26
5 VOLT SUPPLYÐPCM OUTPUT.............26
8-VOLT SUPPLYÐPCM OUTPUT.............26
FUEL CORRECTION or ADAPTIVE MEMORIES . . 26
PROGRAMMABLE COMMUNICATIONS
INTERFACE (PCI) BUS...................27
AIR CONDITIONING PRESSURE
TRANSDUCERÐPCM INPUT..............27
AUTOMATIC SHUTDOWN (ASD) SENSEÐ
PCM INPUT...........................27
BATTERY VOLTAGEÐPCM INPUT............28
BRAKE SWITCHÐPCM INPUT...............28
CAMSHAFT POSITION SENSORÐPCM INPUT . . 28
CLUTCH INTERLOCK/UPSTOP SWITCH.......29
CRANKSHAFT POSITION SENSORÐPCM
INPUT................................30
ENGINE COOLANT TEMPERATURE
SENSORÐPCM INPUT...................30
FUEL LEVEL SENSORÐPCM INPUT..........31
HEATED OXYGEN SENSOR (O2 SENSOR)Ð
PCM INPUT...........................32
IGNITION CIRCUIT SENSEÐPCM INPUT......34
INLET AIR TEMPERATURE SENSORÐPCM
INPUT................................34
KNOCK SENSORÐPCM INPUT..............34
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSORÐPCM INPUT...................35
POWER STEERING PRESSURE SWITCHÐ
PCM INPUT...........................35
SENSOR RETURNÐPCM INPUT.............35
SPEED CONTROLÐPCM INPUT.............36
SCI RECEIVEÐPCM INPUT.................36
PARK/NEUTRAL POSITION SWITCHÐPCM
INPUT................................36
THROTTLE POSITION SENSORÐPCM INPUT . . 36VEHICLE SPEED SIGNAL (VSS)ÐPCM INPUT . . 37
AIR CONDITIONING CLUTCH RELAYÐPCM
OUTPUT..............................38
AUTOMATIC SHUTDOWN RELAYÐPCM
OUTPUT..............................38
CHARGING SYSTEM INDICATOR LAMPÐPCM
OUTPUT..............................38
FUEL PUMP RELAYÐPCM OUTPUT..........38
PROPORTIONAL PURGE SOLENOIDÐPCM
OUTPUT..............................39
GENERATOR FIELDÐPCM OUTPUT..........39
IDLE AIR CONTROL MOTORÐPCM OUTPUT . . . 39
DATA LINK CONNECTOR...................40
FUEL INJECTORSÐPCM OUTPUT...........40
IGNITION COILÐPCM OUTPUT..............40
MALFUNCTION INDICATOR (CHECK ENGINE)
LAMPÐPCM OUTPUT...................41
SPEED CONTROLÐPCM INPUT.............41
SCI RECEIVEÐPCM OUTPUT...............41
TACHOMETERÐPCM OUTPUT..............42
TORQUE CONVERTOR CLUTCH SOLENOIDÐ
PCM OUTPUT..........................42
REMOVAL AND INSTALLATION
THROTTLE BODY........................42
THROTTLE POSITION SENSOR.............43
IDLE AIR CONTROL MOTOR................43
MAP SENSOR...........................44
POWERTRAIN CONTROL MODULE (PCM).....44
UPSTREAM HEATED OXYGEN SENSOR......45
DOWNSTREAM HEATED OXYGEN SENSOR
1/2 ..................................46
AIR CLEANER BOX.......................46
AIR CLEANER ELEMENT...................47
ENGINE COOLANT TEMPERATURE SENSOR . . . 47
VEHICLE SPEED SENSOR.................47
KNOCK SENSOR.........................48
SPECIFICATIONS
VECI LABEL.............................49
TORQUE...............................49
SPECIAL TOOLS
FUEL..................................49
PLFUEL SYSTEM 14 - 21

1 second. Therefore, battery voltage is not supplied to
the fuel pump, ignition coil, fuel injectors and heated
oxygen sensors.
ENGINE START-UP MODE
This is an OPEN LOOP mode. If the vehicle is in
park or neutral (automatic transaxles) or the clutch
pedal is depressed (manual transaxles) the ignition
switch energizes the starter relay. The following
actions occur when the starter motor is engaged.
²If the PCM receives the camshaft position sensor
and crankshaft position sensor signals, it energizes
the Auto Shutdown (ASD) relay and fuel pump relay.
If the PCM does not receive both signals within
approximately one second, it will not energize the
ASD relay and fuel pump relay. The ASD and fuel
pump relays supply battery voltage to the fuel pump,
fuel injectors, ignition coil and heated oxygen sen-
sors.
²The PCM energizes the injectors (on the 69É
degree falling edge) for a calculated pulse width until
it determines crankshaft position from the camshaft
position sensor and crankshaft position sensor sig-
nals. The PCM determines crankshaft position within
1 engine revolution.
²After determining crankshaft position, the PCM
begins energizing the injectors in sequence. It adjusts
injector pulse width and controls injector synchroni-
zation by turning the individual ground paths to the
injectors On and Off.
²When the engine idles within664 RPM of its
target RPM, the PCM compares current MAP sensor
value with the atmospheric pressure value received
during the Ignition Switch On (zero RPM) mode. If
the PCM does not detect a minimum difference
between the two values, it sets a MAP diagnostic
trouble code into memory.
Once the ASD and fuel pump relays have been
energized, the PCM determines injector pulse width
based on the following:
²Battery voltage
²Engine coolant temperature
²Engine RPM
²Intake air temperature (IAT)
²Throttle position
²The number of engine revolutions since cranking
was initiated.
During Start-up the PCM maintains ignition tim-
ing at 9É BTDC.
ENGINE WARM-UP MODE
This is an OPEN LOOP mode. The following inputs
are received by the PCM:
²Engine coolant temperature
²Manifold Absolute Pressure (MAP)
²Intake air temperature (IAT)²Crankshaft position (engine speed)
²Camshaft position
²Knock sensor
²Throttle position
²A/C switch
²Battery voltage
²Power steering pressure switch
²Vehicle speed
²Speed control
²O2 sensors
²All diagnostics
The PCM adjusts injector pulse width and controls
injector synchronization by turning the individual
ground paths to the injectors On and Off.
The PCM adjusts ignition timing and engine idle
speed. Engine idle speed is adjusted through the idle
air control motor.
CRUISE OR IDLE MODE
When the engine is at operating temperature this
is a CLOSED LOOP mode. During cruising or idle
the following inputs are received by the PCM:
²Intake air temperature
²Engine coolant temperature
²Manifold absolute pressure
²Crankshaft position (engine speed)
²Camshaft position
²Knock sensor
²Throttle position
²Exhaust gas oxygen content
²A/C control positions
²Power steering pressure switch
²Battery voltage
²Vehicle speed
The PCM adjusts injector pulse width and controls
injector synchronization by turning the individual
ground paths to the injectors On and Off.
The PCM adjusts engine idle speed and ignition
timing. The PCM adjusts the air/fuel ratio according
to the oxygen content in the exhaust gas (measured
by the upstream and downstream heated oxygen sen-
sor).
The PCM monitors for engine misfire. During
active misfire and depending on the severity, the
PCM either continuously illuminates or flashes the
malfunction indicator lamp (Check Engine light on
instrument panel). Also, the PCM stores an engine
misfire DTC in memory.
The PCM performs several diagnostic routines.
They include:
²Oxygen sensor monitor
²Downstream heated oxygen sensor diagnostics
during open loop operation (except for shorted)
²Fuel system monitor
²EGR monitor
²Purge system monitor
PLFUEL SYSTEM 14 - 23
DESCRIPTION AND OPERATION (Continued)