2000 DODGE NEON engine coolant

CYLINDER HEAD
REMOVAL
(1) Perform fuel system pressure release procedure
before attempting any repairs.Refer to Group 14,
Fuel System
(2) Disconnect negative battery cable.
(3) Remove power steering/air conditioning drive
belt. Refer to Group 7, Cooling System Accessory
Drive for procedure.
(4) Raise vehicle.
(5) Drain cooling system. Refer to Group 7, Cooling
System.
(6) Remove exhaust pipe from manifold.
(7) Remove right front wheel.
(8) Remove right side splash shield.
(9) Remove generator belt. Refer to Group 7, Cool-
ing System Accessory Drive Belts for procedure.
(10) Remove crankshaft damper. Refer to proce-
dure in this section.
(11) Remove lower torque strut.
(12) Lower vehicle and remove upper torque strut.
(13) Remove ground strap and power steering hose
support clip from engine mount bracket.
(14) Remove power steering pump assembly and
set aside.
(15) Support engine from beneath with a suitable
jack.
(16) Remove right side engine mount to bracket
through bolt.
(17) Remove the lower engine mount bracket bolt.
Raise engine slightly and remove the upper engine
mount bracket bolts.(18) Remove engine mount bracket. This procedure
may require additional raising/lowering of engine
until bracket will clear engine components.
(19) Remove front timing belt cover.
(20) Rotate engine until timing marks are aligned.
(21) Remove timing belt and tensioner. Refer to
procedures in this section.
(22) Remove camshaft sprocket. Refer to proce-
dures in this section.
(23) Remove rear timing belt cover.
(24) Disconnect fuel line at fuel rail.
(25) Remove coolant recovery container.
(26) Remove ground wire to cylinder head.
(27) Remove upper radiator hose.
(28) Remove intake manifold. Refer to procedure
in this section.
(29) Disconnect ignition coil electrical connector.
Remove coil pack and spark plug cables from engine.
(30) Remove Crankcase Closed Ventilation (CCV)
hose from cylinder head cover.
(31) Disconnect cam sensor and coolant tempera-
ture electrical connectors.
(32) Remove heater tube to cylinder head attach-
ing fasteners.
(33) Remove heater hose from thermostat housing
connector.
(34) Remove cylinder head cover.
(35) Remove cylinder head bolts.
(36) Remove cylinder head and gasket (Fig. 55).
PL2.0L SOHC ENGINE 9 - 37
REMOVAL AND INSTALLATION (Continued)

(2) Apply MopartGasket Sealant (aerosol can) to
both sides of the new cylinder head gasket.
(3) Position a new cylinder head gasket on the
locating dowels.
(4) Position crankshaft sprocket to TDC, then
rotate crankshaft until mark is three teeth before
TDC (Fig. 59). This will ensure that no piston-to-
valve contact occurs upon installation of cylinder
head in the event of camshaft rotation.
(5) Position the cylinder head onto the cylinder
block. Make sure the cylinder head seats fully over
the locating dowels.
(6) Before installing cylinder head bolts, the
threads should be oiled with engine oil. The 4 shorter
bolts 164 mm (6.45 in.), are to be installed in posi-
tions 7, 8, 9, and 10 (Fig. 60).
(7) Tighten the cylinder head bolts in the sequence
shown in (Fig. 60). Using the 4 step torque method,
tighten according to the following values:²First All to 34 N´m (25 ft. lbs.)
²Second All to 68 N´m (50 ft. lbs.)
²Third All to 68 N´m (50 ft. lbs.)
²Fourth Turn an additional 1/4 Turn.Do not use
a torque wrench for this step.
(8) Install cylinder head cover.
(9) Install heater hose to thermostat housing con-
nector.
(10) Install heater tube to cylinder head attaching
fasteners.
(11) Connect cam sensor and coolant temperature
electrical connectors.
(12) Connect Crankcase Closed Ventilation (CCV)
hose to cylinder head cover.
Fig. 56 Checking Cylinder Head Flatness
1 ± FEELER GAUGE
2 ± STRAIGHT EDGE
Fig. 57 Checking Bolts for Stretching (Necking)
1 ± STRETCHED BOLT
2 ± THREADS ARE NOT STRAIGHT ON LINE
3 ± THREADS ARE STRAIGHT ON LINE
4 ± UNSTRETCHED BOLT
Fig. 58 Proper Tool Usage for Surface Preparation
1 ± ABRASIVE PAD
2 ± 3M ROLOCYBRISTLE DISC
3 ± PLASTIC/WOOD SCRAPER
Fig. 59 Crankshaft Sprocket Position
1 ± TDC MARK
PL2.0L SOHC ENGINE 9 - 39
REMOVAL AND INSTALLATION (Continued)

(13) Install ignition coil and spark plug cables.
Connect coil electrical connector.
(14) Install intake manifold. Refer to procedure in
this section.
(15) Install upper radiator hose.
(16) Install ground wire to cylinder head.
(17) Install coolant recovery container.
(18) Connect fuel line to fuel rail.
(19) Install rear timing belt cover, camshaft
sprocket, and timing belt tensioner and timing belt.
Refer to procedures in this section.
(20) Install front timing belt cover.
(21) Install engine mount bracket.
(22) Position engine and install right side engine
mount to engine mount bracket bolt. Tighten bolt to
118 N´m (87 ft. lbs.). Remove jack from beneath
engine.
(23) Install power steering pump assembly.
(24) Install power steering hose support clip and
ground strap to engine mount bracket.
(25) Install upper torque strut.
(26) Raise vehicle.
(27) Install lower torque strut.
(28) Install crankshaft damper.
(29) Install accessory drive belts. Refer to Group 7,
Cooling System Accessory Drive Belt for procedure.
(30) Install right side splash shield and front
wheel.
(31) Install exhaust pipe to exhaust manifold
flange.
(32) Lower vehicle and fill cooling system. Refer to
Group 7, Cooling System for procedure.
(33) Connect negative cable to battery.
(34) 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.
CRANKSHAFT DAMPER
REMOVAL
(1) Remove accessory drive belts. Refer to Group 7,
Cooling System for procedure.
(2) Raise vehicle on a hoist and remove right inner
splash shield.
(3) Remove crankshaft damper bolt. Remove
damper using the large side of Special Tool 1026 and
insert 6827-A (Fig. 61).
INSTALLATION
(1) Install crankshaft damper using M12±1.75 x
150 mm bolt, washer, thrust bearing and nut from
Special Tool 6792 (Fig. 62).
Fig. 62 Crankshaft DamperÐInstallation
1 ± M12 Ð 1.753150 MM BOLT, WASHER AND THRUST
BEARING FROM SPECIAL TOOL 6792
Fig. 60 Cylinder Head Tightening Sequence
Fig. 61 Crankshaft DamperÐRemoval
1 ± SPECIAL TOOL 6827±A INSERT
2 ± SPECIAL TOOL 1026 THREE JAW PULLER
9 - 40 2.0L SOHC ENGINEPL
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

DESCRIPTION AND OPERATION
INJECTION SYSTEM
All engines used in this section have a sequential
Multi-Port Electronic Fuel Injection system. The MPI
system is computer regulated and provides precise
air/fuel ratios for all driving conditions. The Power-
train Control Module (PCM) operates the fuel injec-
tion system.
The PCM regulates:
²Ignition timing
²Air/fuel ratio
²Emission control devices
²Cooling fan
²Charging system
²Idle speed
²Vehicle speed control
Various sensors provide the inputs necessary for
the PCM to correctly operate these systems. In addi-
tion to the sensors, various switches also provide
inputs to the PCM.
All inputs to the PCM are converted into signals.
The PCM can adapt its programming to meet chang-
ing operating conditions.
Fuel is injected into the intake port above the
intake valve in precise metered amounts through
electrically operated injectors. The PCM fires the
injectors in a specific sequence. Under most operat-
ing conditions, the PCM maintains an air fuel ratio
of 14.7 parts air to 1 part fuel by constantly adjust-
ing injector pulse width. Injector pulse width is the
length of time the injector is open.
The PCM adjusts injector pulse width by opening
and closing the ground path to the injector. Engine
RPM (speed) and manifold absolute pressure (air
density) are the primary inputs that determine injec-
tor pulse width.
MODES OF OPERATION
OPERATION
As input signals to the PCM change, the PCM
adjusts its response to output devices. For example,
the PCM must calculate a different injector pulse
width and ignition timing for idle than it does for
Wide Open Throttle (WOT). There are several differ-
ent modes of operation that determine how the PCM
responds to the various input signals.
There are two different areas of operation, OPEN
LOOP and CLOSED LOOP.
During OPEN LOOP modes the PCM receives
input signals and responds according to preset PCM
programming. Inputs from the upstream and down-
stream heated oxygen sensors are not monitored dur-
ing OPEN LOOP modes, except for heated oxygensensor diagnostics (they are checked for shorted con-
ditions at all times).
During CLOSED LOOP modes the PCM monitors
the inputs from the upstream and downstream
heated oxygen sensors. The upstream heated oxygen
sensor input tells the PCM if the calculated injector
pulse width resulted in the ideal air-fuel ratio of 14.7
to one. By monitoring the exhaust oxygen content
through the upstream heated oxygen sensor, the
PCM can fine tune injector pulse width. Fine tuning
injector pulse width allows the PCM to achieve opti-
mum fuel economy combined with low emissions.
For the PCM to enter CLOSED LOOP operation,
the following must occur:
(1) Engine coolant temperature must be over 35ÉF.
²If the coolant is over 35É the PCM will wait 44
seconds.
²If the coolant is over 50ÉF the PCM will wait 38
seconds.
²If the coolant is over 167ÉF the PCM will wait
11 seconds.
(2) For other temperatures the PCM will interpo-
late the correct waiting time.
(3) O2 sensor must read either greater than 0.745
volts or less than 0.1 volt.
(4) The multi-port fuel injection systems has the
following modes of operation:
²Ignition switch ON (Zero RPM)
²Engine start-up
²Engine warm-up
²Cruise
²Idle
²Acceleration
²Deceleration
²Wide Open Throttle
²Ignition switch OFF
(5) The engine start-up (crank), engine warm-up,
deceleration with fuel shutoff and wide open throttle
modes are OPEN LOOP modes. Under most operat-
ing conditions, the acceleration, deceleration (with
A/C on), idle and cruise modes,with the engine at
operating temperatureare CLOSED LOOP modes.
IGNITION SWITCH ON (ZERO RPM) MODE
When the ignition switch activates the fuel injec-
tion system, the following actions occur:
²The PCM monitors the engine coolant tempera-
ture sensor and throttle position sensor input. The
PCM determines basic fuel injector pulse width from
this input.
²The PCM determines atmospheric air pressure
from the MAP sensor input to modify injector pulse
width.
When the key is in the ON position and the engine
is not running (zero rpm), the Auto Shutdown (ASD)
and fuel pump relays de-energize after approximately
14 - 22 FUEL SYSTEMPL

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)

²All inputs monitored for proper voltage range.
²All monitored components (refer to the Emission
section for On-Board Diagnostics).
The PCM compares the upstream and downstream
heated oxygen sensor inputs to measure catalytic
convertor efficiency. If the catalyst efficiency drops
below the minimum acceptable percentage, the PCM
stores a diagnostic trouble code in memory.
During certain idle conditions, the PCM may enter
a variable idle speed strategy. During variable idle
speed strategy the PCM adjusts engine speed based
on the following inputs.
²A/C sense
²Battery voltage
²Battery temperature
²Engine coolant temperature
²Engine run time
²Power steering pressure switch
²Vehicle mileage
ACCELERATION MODE
This is a CLOSED LOOP mode. The PCM recog-
nizes an abrupt increase in Throttle Position sensor
output voltage or MAP sensor output voltage as a
demand for increased engine output and vehicle
acceleration. The PCM increases injector pulse width
in response to increased fuel demand.
DECELERATION MODE
This is a CLOSED LOOP mode. During decelera-
tion the following inputs are received by the PCM:
²A/C pressure transducer
²A/C sense
²Battery voltage
²Intake air temperature
²Engine coolant temperature
²Crankshaft position (engine speed)
²Exhaust gas oxygen content (upstream heated
oxygen sensor)
²Knock sensor
²Manifold absolute pressure
²Power steering pressure switch
²Throttle position
²IAC motor control changes in response to MAP
sensor feedback.
The PCM may receive a closed throttle input from
the Throttle Position Sensor (TPS) when it senses an
abrupt decrease in manifold pressure. This indicates
a hard deceleration. In response, the PCM may
momentarily turn off the injectors. This helps
improve fuel economy, emissions and engine braking.
If decel fuel shutoff is detected, downstream oxy-
gen sensor diagnostics is performed.WIDE-OPEN-THROTTLE MODE
This is an OPEN LOOP mode. During wide-open-
throttle operation, the following inputs are received
by the PCM:
²Intake air temperature
²Engine coolant temperature
²Engine speed
²Knock sensor
²Manifold absolute pressure
²Throttle position
When the PCM senses a wide-open-throttle condi-
tion through the Throttle Position Sensor (TPS) it de-
energizes the A/C compressor clutch relay. This
disables the air conditioning system.
The PCM does not monitor the heated oxygen sen-
sor inputs during wide-open-throttle operation except
for downstream heated oxygen sensor and both
shorted diagnostics. The PCM adjusts injector pulse
width to supply a predetermined amount of addi-
tional fuel.
IGNITION SWITCH OFF MODE
When the operator turns the ignition switch to the
OFF position, the following occurs:
²All outputs are turned off, unless 02 Heater
Monitor test is being run. Refer to the Emission sec-
tion for On-Board Diagnostics.
²No inputs are monitored except for the heated
oxygen sensors. The PCM monitors the heating ele-
ments in the oxygen sensors and then shuts down.
SYSTEM DIAGNOSIS
OPERATION
The PCM can test many of its own input and out-
put circuits. If the PCM senses a fault in a major
system, the PCM stores a Diagnostic Trouble Code
(DTC) in memory.
For DTC information see On-Board Diagnostics.
POWER DISTRIBUTION CENTER
The Power Distribution Center (PDC) is located
next to the battery (Fig. 1). The PDC contains the
starter relay, radiator fan relay, A/C compressor
clutch relay, auto shutdown relay, fuel pump relay
and several fuses.
POWERTRAIN CONTROL MODULE
The Powertrain Control Module (PCM) is a digital
computer containing a microprocessor (Fig. 2). The
PCM receives input signals from various switches
and sensors that are referred to as PCM Inputs.
Based on these inputs, the PCM adjusts various
engine and vehicle operations through devices that
are referred to as PCM Outputs.
PCM Inputs:
14 - 24 FUEL SYSTEMPL
DESCRIPTION AND OPERATION (Continued)

²Air Conditioning Controls
²Battery Voltage
²Inlet Air/Battery Temperature Sensor
²Brake Switch
²Camshaft Position Sensor
²Crankshaft Position Sensor
²Engine Coolant Temperature Sensor
²Fuel Level Sensor
²Ignition Switch
²Inlet Air/Intake Air Temperature Sensor
²Knock Sensor
²Manifold Absolute Pressure (MAP) Sensor
²Oxygen Sensors
²Power Steering Pressure Switch²SCI Receive
²Speed Control Switches
²Throttle Position Sensor
²Transmission Park/Neutral Switch (automatic
transmission)
²Vehicle Speed Sensor
PCM Outputs:
²Air Conditioning WOT Relay
²Auto Shutdown (ASD) Relay
²Charging Indicator Lamp
²Data Link Connector
²Proportional Purge Solenoid
²EGR Solenoid
²Fuel Injectors
²Fuel Pump Relay
²Generator Field
²Idle Air Control Motor
²Ignition Coils
²Malfunction Indicator (Check Engine) Lamp
²Radiator Fan Relay
²Speed Control Solenoids
²Tachometer
²Torque Convertor Clutch Solenoid
Based on inputs it receives, the PCM adjusts fuel
injector pulse width, idle speed, ignition spark
advance, ignition coil dwell and EVAP canister purge
operation. The PCM regulates the cooling fan, air
conditioning and speed control systems. The PCM
changes generator charge rate by adjusting the gen-
erator field. The PCM also performs diagnostics.
The PCM adjusts injector pulse width (air-fuel
ratio) based on the following inputs.
²Battery voltage
²Coolant temperature
²Inlet Air/Intake air temperature
²Exhaust gas content (oxygen sensor)
²Engine speed (crankshaft position sensor)
²Manifold absolute pressure
²Throttle position
The PCM adjusts ignition timing based on the fol-
lowing inputs.
²Coolant temperature
²Inlet Air/Intake air temperature
²Engine speed (crankshaft position sensor)
²Knock sensor
²Manifold absolute pressure
²Throttle position
²Transmission gear selection (park/neutral
switch)
The PCM also adjusts engine idle speed through
the idle air control motor based on the following
inputs.
²Air conditioning sense
²Battery voltage
²Battery temperature
²Brake switch
Fig. 1 Power Distribution Center (PDC)
Fig. 2 Powertrain Control Module (PCM)
1 ± PCM
PLFUEL SYSTEM 14 - 25
DESCRIPTION AND OPERATION (Continued)