engine overheat DODGE NEON 1999 Service Repair Manual

If old brake shoe return or hold down springs have
overheated or are damaged, replace. Overheating
indications are paint discoloration or distorted end
coils.
REAR DRUM BRAKE WHEEL CYLINDER
With brake drums removed, inspect the wheel cyl-
inder boots for evidence of a brake fluid leak. Visu-
ally check the boots for cuts, tears, or heat cracks. If
any of these conditions exist, the wheel cylinders
should be completely cleaned, inspected and new
parts installed.
If a wheel cylinder is leaking and the brake lining
material is saturated with brake fluid, the brake
shoes must be replaced.
CHASSIS TUBES AND HOSES
Flexible rubber hose is used at both front and rear
brakes. Inspection of brake hoses should be per-
formed whenever the brake system is serviced and
every 7,500 miles or 12 months, whichever comes
first (every engine oil change). Inspect hydraulic
brake hoses for severe surface cracking, scuffing,
worn spots or physical damage. If the fabric casing of
the rubber hose becomes exposed due to cracks or
abrasions in the rubber hose cover, the hose should
be replaced immediately. Eventual deterioration of
the hose can take place with possible burst failure.
Faulty installation can cause twisting, resulting in
wheel, tire, or chassis interference.
The steel brake tubing should be inspected periodi-
cally for evidence of corrosion, physical damage or con-
tact with moving or hot components of the vehicle.
REAR WHEEL HUB AND BEARING ASSEMBLY
The rear hub and bearing assembly is designed for
the life of the vehicle and should require no mainte-
nance. The following procedure may be used for eval-
uation of bearing condition.
With wheel and brake drum removed, rotate
flanged outer ring of hub. Excessive roughness, lat-
eral play or resistance to rotation may indicate dirt
intrusion or bearing failure. If the rear wheel bear-
ings exhibit these conditions during inspection, the
hub and bearing assembly should be replaced.Damaged bearing seals and resulting excessive
grease loss may also require bearing replacement.
Moderate grease loss from bearing is considered nor-
mal and should not require replacement of the hub
and bearing assembly.
ADJUSTMENTS
STOP LAMP SWITCH
(1) Remove stop lamp switch from its bracket by
rotating it approximately 30É in a counter-clockwise
direction.
(2) Disconnect wiring harness connector from stop
lamp switch.
(3) Hold stop lamp switch firmly in one hand.
Then using other hand, pull outward on the plunger
of the stop lamp switch until it has ratcheted out to
its fully extended position.
(4) Install the stop lamp switch into the bracket
using the following procedure. Depress the brake
pedal as far down as possible. Then while keeping
the brake pedal depressed, install the stop lamp
switch into the bracket by aligning index key on
switch with slot at top of square hole in mounting
bracket. When switch is fully installed in the square
hole of the bracket, rotate switch clockwise approxi-
mately 30É to lock the switch into the bracket.
CAUTION: Do not use excessive force when pulling
back on brake pedal to adjust the stop lamp switch.
If too much force is used, damage to the vacuum
booster, stop lamp switch or striker (Fig. 185) can
result.
(5) Connect the wiring harness connector to the
stop lamp switch.
(6) Gently pull back on brake pedal until the pedal
stops moving. This will cause the switch plunger
(Fig. 185) to ratchet backward to the correct position.
REAR DRUM BRAKE SHOE ADJUSTMENT
NOTE: Normally, self adjusting drum brakes will
not require manual brake shoe adjustment.
Although in the event of a brake reline it is advis-
able to make the initial adjustment manually to
speed up the adjusting time.
(1) Raise the vehicle so all wheels are free to turn.
See Hoisting Recommendations in the Lubrication
And Maintenance Section at the front of this service
manual.
(2) Remove rear brake adjusting hole rubber plug
(Fig. 186) from the rear brake shoe support plate.
Fig. 184 Adjuster Screw And Lever (Typical)
PLBRAKES 5 - 65
CLEANING AND INSPECTION (Continued)

DIAGNOSIS AND TESTING
COOLING SYSTEM DIAGNOSIS
CONDITION POSSIBLE CAUSE CORRECTION
TEMPERATURE GAUGE READS
LOW1. Has a Diagnostic Trouble Code
(DTC) been set indicating a stuck
open engine thermostat?1. Refer to On Board Diagnostic in
Group 25. Replace thermostat if
necessary. If a (DTC) has not been
set, the problem may be with the
temperature gauge.
2. Is the temperature gauge (if
equipped) connected to the
temperature gauge coolant sensor
on the engine?2. Check the connector at the
engine coolant sensor. Refer to
Group 8E. Repair as necessary.
3. Is the temperature gauge (if
equipped) operating OK?3. Check Gauge operation. Refer to
Group 8E. Repair as necessary.
4. Coolant level low during cold
ambient temperature, accompanied
by poor heater performance.4. Check coolant level in the coolant
overflow/reserve tank and the
radiator. Inspect the system for
leaks. Repair as necessary. Refer to
WARNINGS outlined in this section
before removing pressure cap.
TEMPERATURE GAUGE READS
HIGH OR ENGINE COOLANT
WARNING LAMP ILLUMINATES.
COOLANT MAY OR MAY NOT BE
LOST FROM SYSTEM.1. Trailer being towed, a steep hill
being climbed, vehicle being
operated in slow moving traffic, or
engine idling during high ambient
(outside) temperatures with air
conditioning on. High altitudes
Could aggravate these conditions.1. This may be a temporary
condition and repair is not
necessary. Turn off the air
conditioning and drive the vehicle
without any of the previous
conditions. Observe the temperature
gauge the gauge should return to
the normal range. If the gauge does
not return to the normal range,
determine the cause of the
overheating and repair. Refer to
POSSIBLE CAUSES in this section.
2. Is temperature gauge (if
equipped) reading correctly?2. Check gauge. Refer to Group 8E.
Repair as necessary.
3. Is temperature warning lamp (if
equipped) illuminating
unnecessarily?3. Check warning lamp operation.
Refer to Group 8E. Repair as
necessary.
4. Coolant low in overflow/reserve
tank and radiator?4. Check for coolant leaks and
repair as necessary. Refer to
checking cooling system for leaks in
this group.
5. Pressure cap not installed tightly.
If cap is loose, boiling point of
coolant will be lowered. Also refer
to the following step 6.5. Tighten cap.
6. Poor seals at radiator cap. 6. (a) Check condition of cap and
cap seals. Refer to Radiator cap
Inspection. Replace cap if
necessary.
6. (b) Check condition of filler neck.
If neck is bent or damaged, replace
neck.
PLCOOLING 7 - 7

COOLING SYSTEM DIAGNOSIS CONT.
CONDITION POSSIBLE CAUSES CORRECTION
INADEQUATE AIR CONDITIONER
PERFORMANCE (COOLING
SYSTEM SUSPECTED)1. Radiator and/or air conditioning
condenser is restricted, obstructed
or dirty.1. Remove restriction and/or clean
as necessary.
2. Electric radiator fan not operating
when a/c is on.2. Refer to appropriate Powertrain
Diagnostic Procedures manual for
operation of the DRB scan tool.
repair as necessary.
3. Engine is overheating ( heat may
be transferred from radiator to A/C
condenser. High underhood
temperature due to engine
overheating may also transfer heat
to A/C components).3. Correct overheating condition.
Refer to Group 7, Cooling.
INADEQUATE HEATER
PERFORMANCE.1. Has a diagnostic trouble code
(DTC) been set?1. Refer to On-Board Diagnostic in
Group 25, and replace thermostat if
necessary.
2. Coolant level low. 2. Refer to testing cooling system
for leaks in this section. Repair as
necessary.
3. Obstructions in heater hose
fittings at engine.3. Remove heater hoses at both
ends and check for obstructions.
Repair as necessary.
4. Heater hose kinked. 4. Locate kinked area and repair as
necessary.
5. Water pump is not pumping
coolant to heater core. When the
engine is fully warmed up, both
heater hoses should be hot to the
touch. The accessory drive belt
may be slipping causing poor water
pump operation.5. Refer to water pump in this
group. Repair as necessary. If
slipping belt is detected, refer to
accessory drive belts in this group.
Repair as necessary.
HEAT ODOR 6. Various heat shields are used at
certain drive line components. One
or more of these shields may be
missing.6. Locate missing shields and
replace or repair as necessary.
PLCOOLING 7 - 11
DIAGNOSIS AND TESTING (Continued)

(1) Connect a volt-ampere tester to the battery ter-
minals (Fig. 7). Refer to the operating instructions
provided with the tester being used.
(2) To disable the ignition and fuel systems, dis-
connect the Automatic Shutdown Relay (ASD). The
ASD relay is located in the Power Distribution Cen-
ter (PDC). Refer to the PDC cover for proper relay
location. The 2.5L Diesel Engine, to disable the
engine from starting, disconnect wire connector from
the Fuel Solenoid.
(3) Verify that all lights and accessories are OFF,
and the transmission shift selector is in the PARKposition or with the clutch pedal depressed and SET
parking brake.
CAUTION: Do not overheat the starter motor or
draw the battery voltage below 9.6 volts during
cranking operations.
(4) Rotate and hold the ignition switch in the
START position. Observe the volt-ampere tester (Fig.
6).
²If voltage reads above 9.6 volts, and amperage
draw reads above 280 amps or the Diesel engine
above 450 amps, check for engine seizing or faulty
starter.
²If voltage reads 12.4 volts or greater and amper-
age reads 0 to 10 amps, check for corroded cables
and/or bad connections.
²Voltage below 9.6 volts and amperage draw
above 300 amps or Diesel engine above 500 amps,
the problem is the starter. Replace the starter refer
to starter removal.
(5) After the starting system problems have been
corrected, verify the battery state-of-charge and
Fig. 6 Volt Ampere Tester
Fig. 7 Volt-Ampere Tester Connections
Fig. 4 Test Starter Motor Ground
Fig. 5 Test Battery Positive Cable Resistance
PLSTARTING 8B - 3
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)

NOTE: Transaxle operation requirements are differ-
ent for each vehicle and engine combination. Some
internal parts will be different to provide for this.
Therefore, when replacing parts, refer to the seven
digit part number stamped on rear of the transaxle
oil pan flange.
Within this transaxle, there are three primary
areas:
(1) Main center line plus valve body.
(2) Transfer shaft center line (includes governor
and parking sprag).
(3) Differential center line.
Center distances between the main rotating parts
in these three areas are held precise to maintain a
low noise level.
The torque converter, transaxle area, and differen-
tial are housed in an integral aluminum die casting.
The differential oil sump is common with the
transaxle sump. Separate filling of the differen-
tial is NOT necessary.
The torque converter is attached to the crankshaft
through a flexible driving plate. Cooling of the con-
verter is accomplished by circulating the transaxle
fluid through a remote cooler. There are two types of
coolers used. An oil-to-water type cooler located in
the radiator side tank and/or an oil-to-air heat
exchanger. The torque converter assembly is a sealed
unit that cannot be disassembled.
The transaxle fluid is filtered by an internal filter
attached to the lower side of the valve body assembly.
Engine torque is transmitted to the torque con-
verter and then through the input shaft to multiple-
disc clutches in the transaxle. The power flow
depends on the application of the clutches and bands.
Refer to Elements in Use Chart in Diagnosis and
Tests section.
The transaxle consists of:
²Two multiple-disc clutches
²An overrunning clutch
²Two servos
²A hydraulic accumulator
²Two bands
²Two planetary gear sets
This provides three forward ratios and a reverse
ratio. The common sun gear of the planetary gear
sets is connected to the front clutch by a driving
shell. The driving shell is splined to the sun gear and
front clutch retainer. The hydraulic system consists
of an oil pump and a single valve body which con-
tains all of the valves except the governor valves.
The transaxle sump and differential sump are both
vented through the dipstick. Output torque from the
main center line is delivered through helical gears to
the transfer shaft. This gear set is a factor in the
transaxle final drive (axle) ratio. The shaft also car-
ries the governor and parking sprag. An integral heli-cal gear on the transfer shaft drives the differential
ring gear. The final drive gearing is completed with
one of two gear ratios; 2.98 or 3.19 depending on
model and application.
FLUID LEVEL AND CONDITION
NOTE: The transmission and differential sump have
a common oil sump with a communicating opening
between the two.
The torque converter fills in both the P (Park) and
N (Neutral) positions. Place the selector lever in P
(Park) to be sure that the fluid level check is accu-
rate.The engine should be running at idle
speed for at least one minute, with the vehicle
on level ground. This will ensure complete oil
level stabilization between differential and
transmission.The fluid should be at normal operat-
ing temperature (approximately 82É C. or 180É F.).
The fluid level is correct if it is in the HOT region
(cross-hatched area) on the dipstick.
Low fluid level can cause a variety of conditions,
because it allows the pump to take in air along with
the fluid. As in any hydraulic system, air bubbles
make the fluid spongy therefore, pressures will be
low and will build up slowly.
Improper filling also can raise the fluid level too
high. When the transaxle has too much fluid, the
gears churn up foam and cause the same conditions
that occur with a low fluid level.
In either case, the air bubbles can cause overheat-
ing, fluid oxidation, and varnishing. This can inter-
fere with normal valve, clutch, and servo operation.
Foaming also can result in fluid escaping from the
transaxle dipstick, where it may be mistaken for a
leak.
Along with fluid level, it is important to check the
condition of the fluid. When the fluid smells burned,
or is contaminated with metal or friction material
particles, a complete transaxle overhaul is needed.
Be sure to examine the fluid on the dipstick closely.
If there is any doubt about its condition, drain out a
sample for a double check.
SELECTION OF LUBRICANT
It is important that the proper lubricant be used in
these transmissions. Mopar ATF PLUS 3 (Automatic
Transmission Fluid- type 7176) should be used to aid
in ensuring optimum transmission performance. It is
important that the transmission fluid be maintained
at the prescribed level using the recommended fluids.
SPECIAL ADDITIVES
Chrysler Corporation does not recommend the
addition of any fluids to the transmission, other than
that fluid listed above. An exception to this policy is
PLTRANSAXLE 21 - 41
GENERAL INFORMATION (Continued)

of the test will determine if engine vacuum (full-man-
ifold) is flowing from the inlet to the outlet side of
the valve. This is not to be used as a complete test of
the EGR system.
(1) Disconnect the rubber back-pressure hose from
the fitting at the bottom of EGR valve (Fig. 3).
(2) Connect a hand-held vacuum pump to this fit-
ting.
(3) Apply 10 inches of vacuum to this fitting.
(4) If vacuum falls off, the valve diaphragm is
leaking.
(5) Replace the Complete EGR valve assembly.
Proceed to next step for further testing.
(6) Reconnect hose to EGR valve.
(7) Remove the vacuum supply hose at the vacuum
inletfitting (Fig. 3) on the EGR solenoid.
(8) Connect a vacuum gauge to this disconnected
vacuum line.
(9) Start the engine and bring to operating tem-
perature. Hold engine speed at approximately 1500
rpm.
(10) Check for steady engine vacuum (full-mani-
fold) at this hose.
(11) If engine vacuum (full-manifold) is not
present, check vacuum line to engine and repair as
necessary before proceeding to next step.
(12) Reconnect the rubber hose to the vacuum
inletfitting (Fig. 3) on the EGR valve.
(13) Disconnect the rubber hose at the vacuum
outletfitting (Fig. 3) on the EGR valve.
(14) Connect a vacuum gauge to this fitting.
(15) Disconnect the electrical connector (Fig. 3) at
the valve control. This will simulate an open circuit
(no ground from the PCM) at the valve, activating
the valve. A DTC will be set in the PCM that must
be erased after testing is complete.
(16) Start the engine and bring to operating tem-
perature.
(17) Hold the engine speed to approximately 2000
rpm while checking for engine vacuum (full-manifold)
at this fitting.To allow full manifold vacuum to
flow through the valve, exhaust back-pressure
must be present at valve. It must be high
enough to hold the bleed valve in the trans-
ducer portion of the valve closed.Have a helper
momentarily (a second or two) hold a rag over the
tailpipe opening to build some exhaust back-pressure
while observing the vacuum gauge. Heavy gloves
should be worn.Do not cover the tailpipe open-
ing for an extended period of time as damage to
components or overheating may result.(18) As temporary back-pressure is built, full man-
ifold vacuum should be observed at the vacuum out-
let fitting. Without back-pressure, and engine at
approximately 2000 rpm, the gauge reading will be
low. This low reading is normal. At idle speed, the
gauge reading may be erratic. This is also normal.
(19) If full manifold vacuum is not present at the
outlet fitting, but was present at the inlet fitting,
replace the valve. Note: The EGR valve, valve control
and attaching hoses are serviced as one assembly.
Refer to EGR Valve Removal/Installation in this
group.
REMOVAL AND INSTALLATION
EGR VALVE
If the EGR system operates incorrectly, replace the
entire EGR valve and transducer together. The EGR
valve and electrical transducer are calibrated
together.
REMOVAL
The EGR valve attaches to the rear of the cylinder
head (Fig. 5). EGR transducer is attached to the air
inlet duct.
(1) Remove EGR transducer from air inlet duct.
(2) Disconnect vacuum supply tube from EGR
transducer solenoid.
(3) Disconnect electrical connector from solenoid.
(4) Remove air inlet duct.
(5) Remove EGR tube to EGR valve screws.
(6) Remove EGR valve mounting screws. Remove
EGR valve and transducer.
(7) Clean gasket surfaces. Discard old gaskets. If
necessary, clean EGR passages.
INSTALLATION
(1) Loosely install EGR valve with new gaskets.
(2) Finger tighten EGR tube fasteners.
(3) Tighten EGR tube fasteners to 11 N´m (95 in.
lbs.) torque.
(4) Tightening EGR valve mounting screws to 22
N´m (200 in. lbs.) torque.
(5) Install air inlet duct.
(6) Connect vacuum supply tube to solenoid.
(7) Attach electrical connector to solenoid.
(8) Install EGR transducer onto air inlet duct.
PLEMISSION CONTROL SYSTEMS 25 - 21
DIAGNOSIS AND TESTING (Continued)