1999 DODGE NEON engine

ELECTRODE GAP BRIDGING
Loose deposits in the combustion chamber can
cause electrode gap bridging. The deposits accumu-
late on the spark plugs during continuous stop-
and-go driving. When the engine is suddenly
subjected to a high torque load, the deposits partially
liquefy and bridge the gap between the electrodes
(Fig. 23). This short circuits the electrodes.Spark
plugs with electrode gap bridging can be
cleaned and reused.
SCAVENGER DEPOSITS
Fuel scavenger deposits may be either white or yel-
low (Fig. 24). They may appear to be harmful, but
are a normal condition caused by chemical additives
in certain fuels. These additives are designed tochange the chemical nature of deposits and decrease
spark plug misfire tendencies. Notice that accumula-
tion on the ground electrode and shell area may be
heavy but the deposits are easily removed.Spark
plugs with scavenger deposits can be consid-
ered normal in condition, cleaned and reused.
CHIPPED ELECTRODE INSULATOR
A chipped electrode insulator usually results from
bending the center electrode while adjusting the
spark plug electrode gap. Under certain conditions,
severe detonation also can separate the insulator
from the center electrode (Fig. 25).Spark plugs
with chipped electrode insulators must be
replaced.
PREIGNITION DAMAGE
Excessive combustion chamber temperature can
cause preignition damage. First, the center electrode
dissolves and the ground electrode dissolves some-
what later (Fig. 26). Insulators appear relatively
deposit free. Determine if the spark plugs are the
correct type, as specified on the VECI label, or if
Fig. 22 Oil or Ash Encrusted
Fig. 23 Electrode Gap Bridging
Fig. 24 Scavenger Deposits
Fig. 25 Chipped Electrode Insulator
PLIGNITION SYSTEM 8D - 11
DIAGNOSIS AND TESTING (Continued)

other operating conditions are causing engine over-
heating.
SPARK PLUG OVERHEATING
Overheating is indicated by a white or gray center
electrode insulator that also appears blistered (Fig.
27). The increase in electrode gap will be consider-
ably in excess of 0.001 in per 1000 miles of operation.
This suggests that a plug with a cooler heat range
rating should be used. Over advanced ignition tim-
ing, detonation and cooling system malfunctions also
can cause spark plug overheating.
REMOVAL AND INSTALLATION
POWERTRAIN CONTROL MODULE (PCM)
The PCM attaches to the inner fender panel next
to the washer fluid bottle on the driver's side (Fig.
28).
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove positive cable from battery.(3) Remove the washer bottle neck from the rubber
grommet.
(4) Remove screws attaching PCM to body.
(5) Lift PCM up and disconnect two 40-way con-
nectors.
INSTALLATION
(1) Attach two 40-way connectors to PCM.
(2) Install PCM. Tighten mounting screws to 6.75
N´m61 N´m (60 in. lbs.610 in. lbs.) torque.
(3) Install washer bottle neck into the rubber
grommet.
(4) Connect positive cable to battery.
(5) Connect negative cable to battery.
SPARK PLUG SERVICE
Failure to route the cables properly could cause the
radio to reproduce ignition noise, cross ignition of the
spark plugs or short circuit the cables to ground.
REMOVAL
REMOVE CABLES FROM COIL FIRST.
Always remove the spark plug cable by grasping
the top of the spark plug insulator, turning the boot
1/2 turn and pulling straight up in a steady motion.
(1) Remove the spark plug using a quality socket
with a rubber or foam insert.
(2) Inspect the spark plug condition. Refer to
Spark Plug Condition in this section.
INSTALLATION
(1) To avoid cross threading, start the spark plug
into the cylinder head by hand.
(2) Tighten spark plugs to 28 N´m (20 ft. lbs.)
torque.
(3) Install spark plug insulators over spark plugs.
Ensure the top of the spark plug insulator covers the
upper end of the spark plug tube.
Reconnect to coil.
Fig. 26 Preignition Damage
Fig. 27 Spark Plug Overheating
Fig. 28 Powertrain Control Module
8D - 12 IGNITION SYSTEMPL
DIAGNOSIS AND TESTING (Continued)

SPARK PLUG CABLE SERVICE
Failure to route the cables properly could cause the
radio to reproduce ignition noise, cross ignition of the
spark plugs or short circuit the cables to ground.
REMOVAL
Remove spark plug cable from coil frist.
Always remove the spark plug cable by grasping
the top of the spark plug insulator, turning the boot
1/2 turn and pulling straight up in a steady motion.
INSTALLATION
Install spark plug insulators over spark plugs.
Ensure the top of the spark plug insulator covers the
upper end of the spark plug tube.The connect the
other end to coil pack. OnSOHCengines, be sure
that dual plastic clip holds #1,#2 cables off of valve
cover and that PCV hose plastic clip holds #3 cable
away from metal PCV clamp and edge of air duct. On
DOHC, be sure that the plastic clip on PCV hose is
positioned so that cable clip is beneath hose, and that
#1 cable is snapped into this clip to protect it from
metal PCV clamp.
SPARK PLUG TUBES
The spark plugs tubes are pressed into the cylinder
head. Sealant is applied to the end of the tube before
installation. For engine information, refer to Group
9, Engines.
IGNITION COIL
SOHC/DOHC
The electronic ignition coil pack attaches directly
to the valve cover (Fig. 29) or (Fig. 30).
REMOVAL
(1) Disconnect electrical connector from coil pack.
(2) Remove coil pack mounting nuts.
(3) Remove coil pack.
INSTALLATION
(1) Install coil pack on valve cover.
(2) Transfer spark plug cables to new coil pack.
The coil pack towers are numbered with the cylinder
identification. Be sure the ignition cables snap onto
the towers.
AUTOMATIC SHUTDOWN RELAY
The relay is located in the Power Distribution Cen-
ter (PDC) (Fig. 31). The PDC is located next to the
battery in the engine compartment. For the location
of the relay within the PDC, refer to the PDC cover
for location. Check electrical terminals for corrosion
and repair as necessary.CAMSHAFT POSITION SENSORÐSOHC
The camshaft position sensor is mounted to the
rear of the cylinder head (Fig. 32).
REMOVAL
(1) Disconnect the filtered air tube from the throt-
tle body and air cleaner housing. Remove filtered air
tube.
Fig. 29 Electronic Ignition Coil PackÐSOHC
Fig. 30 Electronic Ignition Coil PackÐDOHC
Fig. 31 Power Distribution Center (PDC)
PLIGNITION SYSTEM 8D - 13
REMOVAL AND INSTALLATION (Continued)

(2) Remove the air cleaner inlet tube.
(3) Disconnect electrical connectors from engine
coolant sensor and camshaft position sensor.
(4) Remove brake booster hose and electrical con-
nector from holders on end of cylinder head cover.
(5) Remove camshaft position sensor mounting
screws. Remove sensor.
(6) Loosen screw attaching target magnet to rear
of camshaft (Fig. 33).
INSTALLATION
The target magnet has two locating dowels that fit
into machined locating holes in end of the camshaft.
(1) Install target magnet in end of camshaft.
Tighten mounting screw to 3.4 N´m (30 in. lbs.)
torque.
(2) Install camshaft position sensor. Tighten sensor
mounting screws to 9 N´m (80 in. lbs.) torque.
(3) Place brake booster hose and electrical harness
in holders on end of valve cover.
(4) Attach electrical connectors to coolant tempera-
ture sensor and camshaft position sensor.(5) Install air cleaner inlet tube and filtered air
tube.
CAMSHAFT POSITION SENSORÐDOHC
The camshaft position sensor is mounted to the
rear of the cylinder head (Fig. 34).
REMOVAL
(1) Remove filtered air tube from the throttle body
and air cleaner housing.
(2) Disconnect electrical connector from camshaft
position sensor.
(3) Remove camshaft position sensor mounting
screws. Remove sensor.
(4) Loosen screw attaching target magnet to rear
of camshaft (Fig. 35).
INSTALLATION
The target magnet has locating dowels that fit into
machined locating holes in the end of the camshaft
(Fig. 36).
Fig. 32 Camshaft Position Sensor LocationÐSOHC
Fig. 33 Target Magnet Removal/Installation
Fig. 34 Camshaft Position Sensor LocationÐDOHC
Fig. 35 Target Magnet Removal/Installation
8D - 14 IGNITION SYSTEMPL
REMOVAL AND INSTALLATION (Continued)

(1) Install target magnet in end of camshaft.
Tighten mounting screw to 3 N´m (30 in. lbs.) torque.
(2) Install camshaft position sensor. Tighten sensor
mounting screws to 9 N´m (80 in. lbs.) torque.
(3) Carefully attach electrical connector to cam-
shaft position sensor. Installation at an angle may
damage the sensor pins.
(4) Install filtered air tube. Tighten clamps to 3
N´m61 (25 in. lbs.65) torque.
CRANKSHAFT POSITION SENSOR
The crankshaft position sensor mounts to the
engine block behind the generator, just above the oil
filter (Fig. 37).
REMOVAL
(1) Disconnect electrical connector from crankshaft
position sensor.
(2) Remove sensor mounting screw. Remove sensor.
INSTALLATION
Reverse procedure for installation.
COMBINATION ENGINE COOLANT TEMPERATURE
SENSORÐSOHC
The combination engine coolant sensor is located at
the rear of the cylinder head next to the camshaft
position sensor (Fig. 38). New sensors have sealant
applied to the threads.
REMOVAL
(1) With the engine cold, drain the cooling system
until coolant level drops below sensor. Refer to Group
7, Cooling System.
(2) Disconnect coolant sensor electrical connector.
(3) Remove coolant sensor
INSTALLATION
(1) Install coolant sensor. Tighten sensor to 18.6
N´m (165 in. lbs.) torque.
(2) Attach electrical connector to sensor.
(3) Fill cooling system. Refer to Group 7, Cooling
System.
COMBINATION ENGINE COOLANT TEMPERATURE
SENSORÐDOHC
The coolant sensor threads into the intake mani-
fold next to the thermostat housing (Fig. 39). New
sensors have sealant applied to the threads.
REMOVAL
(1) With the engine cold, drain coolant until level
drops below cylinder head. Refer to Group 7, Cooling
System.
(2) Disconnect coolant sensor electrical connector.
(3) Remove coolant sensor.
INSTALLATION
(1) Install coolant sensor. Tighten sensor to 18.6
N´m (165 in. lbs.) torque.
(2) Attach electrical connector to sensor.
(3) Fill cooling system. Refer to Group 7, Cooling
System.
Fig. 36 Target Magnet Installation
Fig. 37 Crankshaft Position Sensor
Fig. 38 Engine Coolant Temperature Sensor
PLIGNITION SYSTEM 8D - 15
REMOVAL AND INSTALLATION (Continued)

MAP/IAT SENSORÐSOHC
Refer to Group 14, Fuel Injection Section for
Removal/Installation.
MAP/IAT SENSORÐDOHC
Refer to Group 14, Fuel Injection Section for
Removal/Installation..
THROTTLE POSITION SENSOR
Refer to Group 14, Fuel Injection Section, for
Removal/Installation.
IGNITION SWITCH
The ignition switch attaches to the lock cylinder
housing on the end opposite the lock cylinder (Fig.
40). For ignition switch terminal and circuit identifi-
cation, refer to Group 8W, Wiring Diagrams.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Place key cylinder in RUN position. Through
the hole in the lower shroud, depress lock cylinder
retaining tab and remove key cylinder (Fig. 41).
(3) Remove upper and lower shrouds from steering
column.
(4) Disconnect electrical connectors from ignition
switch.
(5) Remove ignition switch mounting screw (Fig.
42) with a #10 Torxtbit.
(6) Depress retaining tabs (Fig. 43) and pull igni-
tion switch from steering column.
INSTALLATION
(1) Ensure the ignition switch is in the RUN posi-
tion and the actuator shaft in the lock housing is in
the RUN position.
(2) Carefully install the ignition switch. The
switch will snap over the retaining tabs (Fig. 44).
Install mounting screw (Fig. 42).
Fig. 39 Engine Coolant Temperature SensorÐDOHC
Fig. 40 Ignition SwitchÐViewed From Below
Column
Fig. 41 Steering Column Shrouds
Fig. 42 Ignition Switch Mounting Screw
8D - 16 IGNITION SYSTEMPL
REMOVAL AND INSTALLATION (Continued)

IGNITION INTERLOCK
Refer to Group 21, Transaxle for Shifter/Ignition
Interlock Service.
LOCK CYLINDER HOUSING
Refer to Steering Column in Group 19, Steering,
for Lock Cylinder Housing Service.
SPECIFICATIONS
VECI LABEL
If anything differs between the specifications found
on the Vehicle Emission Control Information (VECI)
label and the following specifications, use specifica-
tions on VECI label. The VECI label is located in the
engine compartment.
FIRING ORDERÐ2.0LTORQUE SPECIFICATION
DESCRIPTION TORQUE
Camshaft Position Sensor
Screw.....................9N´m(80in.lbs.)
SOHC Cam Magnet/Target.....3.4 N´m (30 in. lbs.)
DOHC Cam Magnet/Target......3N´m(30in.lbs.)
Crankshaft Position
Sensor Screw...............9N´m(80in.lbs.)
Coolant Temp. Sensor.......18.6 N´m (165 in. lbs.)
Ignition Coil to Cyl. Head.....22N´m(200 in. lbs.)
Ignition Coil Bracket Nuts.....22N´m(200 in. lbs.)
Knock Sensor................10N´m(90in.lbs.)
MAP/IAT Sensor Plastic
Manifold...................2N´m(20in.lbs.)
MAP/IAT Sensor Aluminum
Manifold...................3N´m(30in.lbs.)
Spark Plugs.................28N´m(20ft.lbs.)
SPARK PLUG CABLE RESISTANCEÐSOHC
SPARK PLUG CABLE RESISTANCEÐDOHC
CABLE RESISTANCE
#1,#4 3500 ohmsÐ 4900 ohms
#2,#3 2950 ohmsÐ 4100 ohms
CABLE RESISTANCE
#1,#4 3050 ohmsÐ 4250 ohms
#2,#3 2300 ohmsÐ 3300 ohms
8D - 18 IGNITION SYSTEMPL
REMOVAL AND INSTALLATION (Continued)

SPARK PLUG
IGNITION COIL
Coil Polarity
Engine Spark Plug Gap Thread Size
2.0L RC9YC 0.033 TO 0.038 14mm (3/4 in.) reach
Coil ManufacturePrimary Resistance at 21ÉC-27ÉC
(70ÉF-80ÉF)Secondary Resistance at 21ÉC-
27ÉC (70ÉF-80ÉF)
Weastec (Steel Towers) 0.45 to 0.65 Ohms 7,000 to 15,800 Ohms
PLIGNITION SYSTEM 8D - 19
SPECIFICATIONS (Continued)