Dodge Neon / Neon SRT-4. Manual - part 64

CONDITION

POSSIBLE CAUSE

CORRECTION

9. Air leak on the suction side of
water pump allows air to build up in
cooling system. This will cause the
thermostat to open late.

9. Locate leak and repair as
necessary.

PRESSURE CAP IS BLOWING
OFF STEAM AND/OR COOLANT
FLOWING INTO RECOVERY
CONTAINER. TEMPERATURE
GAUGE READING MAY BE ABOVE
NORMAL, BUT NOT HIGH.
COOLANT LEVEL MAY BE HIGH
IN RECOVERY CONTAINER.

1. Pressure relief valve in pressure
cap is defective.

1. Check condition of radiator
pressure cap and seals. Replace as
necessary. (Refer to 7 - COOLING/
ENGINE/RADIATOR PRESSURE
CAP - DIAGNOSIS AND TESTING)

COOLANT LOSS TO THE
GROUND WITHOUT PRESSURE
CAP BLOWOFF. GAUGE IS
READING HIGH OR HOT.

1. Coolant leaks in radiator, cooling
system hoses, water pump or
engine.

1. Pressure test and repair as
necessary. (Refer to 7 - COOLING/
ENGINE - DIAGNOSIS AND
TESTING).

DETONATION OR PRE-IGNITION
(NOT CAUSED BY IGNITION
SYSTEM). GAUGE MAY OR MAY
NOT BE READING HIGH.

1. Engine overheating.

1. Check reason for overheating
and repair as necessary.

2. Freeze point of coolant not
correct.

2. Check the freeze point of the
coolant. (Refer to 7 - COOLING/
ENGINE/COOLANT - DIAGNOSIS
AND TESTING) Adjust glycol-to-
water ratio as required.

HOSE OR HOSES COLLAPSE
WHEN ENGINE IS COOLING

1. Vacuum created in cooling
system on engine cool-down is not
being relieved through coolant
recovery/reserve container system.

1. (a) Radiator pressure cap relief
valve stuck. (Refer to 7 - COOLING/
ENGINE/RADIATOR PRESSURE
CAP - DIAGNOSIS AND TESTING)
Replace as necessary.

(b) Hose between coolant
recovery/reserve container and
radiator is kinked. Repair as
necessary.

(d) Recovery/reserve container is
internally blocked or plugged. Check
for blockage and repair as
necessary.

ELECTRIC RADIATOR FAN
OPERATES ALL THE TIME.

1. Fan relay, powertrain control
module (PCM) or engine coolant
temperature sensor defective.

1. (Refer to the Appropriate
Diagnostic Information) Repair as
necessary.

2. Check for low coolant level.

2. (Refer to 7 - COOLING/ENGINE -
STANDARD PROCEDURE). Repair
as necessary.

7 - 14

ENGINE - 2.0L SOHC

PL/SRT-4

ENGINE - 2.0L SOHC (Continued)

CONDITION

POSSIBLE CAUSE

CORRECTION

ELECTRIC RADIATOR FAN WILL
NOT OPERATE. GAUGE READING
HIGH OR HOT

1. Radiator fan motor defective.

1. (Refer to the Appropriate
Diagnostic Information) Repair as
necessary.

2. Radiator fan relay, powertrain
control module (PCM) or engine
coolant temperature sensor
defective.

2. (Refer to the Appropriate
Diagnostic Information) Repair as
necessary.

3. Blown fuse in power distribution
center (PDC).

3. Determine reason for blown fuse
and repair as necessary.

NOISY FAN

1. Radiator fan blade loose.

1. Replace fan blade assembly.
(Refer to 7 - COOLING/ENGINE/
RADIATOR FAN - DISASSEMBLY)

2. Radiator fan blade striking a
surrounding object.

2. Locate point of fan blade contact
and repair as necessary.

3. Air obstructions at radiator or A/C
condenser.

3. Remove obstructions and/or
clean debris from radiator and/or
A/C condenser.

4. Radiator fan motor defective.

4. Replace as necessary. (Refer to
7 - COOLING/ENGINE/RADIATOR
FAN - DISASSEMBLY)

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 the Appropriate
Diagnostic Information) 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.

PL/SRT-4

ENGINE - 2.0L SOHC

7 - 15

ENGINE - 2.0L SOHC (Continued)

CONDITION

POSSIBLE CAUSE

CORRECTION

INADEQUATE HEATER
PERFORMANCE.

1. Diagnostic Trouble Code (P0125
or P1281) set indicating a stuck
open engine thermostat

1. (Refer to the Appropriate
Diagnostic Information)

2. Coolant level low.

2. (Refer to 7 - COOLING -
DIAGNOSIS AND TESTING) 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.

5. (Refer to 7 - COOLING/ENGINE/
WATER PUMP - DIAGNOSIS AND
TESTING) Repair as necessary.

HEAT ODOR

1. Various heat shields are used at
certain driveline components. One
or more of these shields may be
missing.

1. Locate missing shields and
replace or repair as necessary.

2. Is temperature gauge reading
above the normal range?

2. Refer to the previous
Temperature Gauge Reads High in
these Diagnostic Charts. Repair as
necessary.

3. Radiator fan operating
incorrectly.

3. (Refer to 7 - COOLING/ENGINE/
RADIATOR FAN - DIAGNOSIS AND
TESTING) Repair as necessary.

4. Has undercoating been applied
to any unnecessary component?

4. Clean undercoating as necessary.

5. Engine may be running rich
causing the catalytic converter to
overheat.

5. (Refer to the Appropriate
Diagnostic Information) Repair as
necessary.

POOR DRIVEABILITY
(THERMOSTAT POSSIBLY STUCK
OPEN). GAUGE MAY BE READING
LOW

1. For proper driveability, good
vehicle emissions and for
preventing build-up of engine oil
sludge, the thermostat must be
operating properly. Has a diagnostic
trouble code (DTC ) been set?

1. (Refer to the Appropriate
Diagnostic Information) Replace
thermostat if necessary.

STEAM IS COMING FROM FRONT
OF VEHICLE NEAR GRILL AREA
WHEN WEATHER IS WET,
ENGINE IS WARMED UP,
RUNNING, AND VEHICLE IS
STATIONARY. TEMPERATURE
GAUGE IS IN NORMAL RANGE.

1. During wet weather, moisture
(snow, ice or rain condensation) on
the radiator will evaporate when the
thermostat opens. This opening
allows heated water into the
radiator. When the moisture contact
the hot radiator, steam may be
emitted. This usually occurs in cold
weather with no fan or airflow to
blow it away.

1. Occasional steam emitting from
this area is normal. No repair is
necessary.

7 - 16

ENGINE - 2.0L SOHC

PL/SRT-4

ENGINE - 2.0L SOHC (Continued)

CONDITION

POSSIBLE CAUSE

CORRECTION

COOLANT COLOR

1. Coolant color is not necessarily
an indication of adequate corrosion
or temperature protection. Do not
rely on coolant color for determining
condition of coolant.

1. Check the freeze point of the
coolant. (Refer to 7 - COOLING/
ENGINE/COOLANT - DIAGNOSIS
AND TESTING) Adjust the
glycol-to-water ratio as required.

COOLANT LEVEL CHANGES IN
COOLANT RECOVERY/RESERVE
CONTAINER

1. Level changes are to be
expected as coolant volume
fluctuates with engine temperature.
If the level in the container was
between the FULL and ADD marks
at normal engine operating
temperature, the level should return
to within that range after operation
at elevated temperatures.

1. A normal condition. No repair is
necessary.

DIAGNOSIS AND TESTING - COOLING SYSTEM
FLOW CHECK

To determine whether coolant is flowing through the

cooling system, use one of the following procedures:

PREFERRED METHOD

WARNING: DO NOT REMOVE THE COOLING SYS-
TEM PRESSURE CAP OR ANY HOSE WITH THE
SYSTEM HOT AND UNDER PRESSURE BECAUSE
SERIOUS BURNS FROM COOLANT CAN OCCUR.

• Remove pressure cap when engine is cold.

Remove small amount of coolant. Idle engine until
thermostat opens. You should observe coolant flow
while looking down the filler neck. Once flow is
detected install the pressure cap. Replace removed
coolant into coolant recovery container.

ALTERNATIVE METHOD

• If engine is cold, idle engine until normal oper-

ating temperature is reached. Feel the upper radiator
hose. If it is hot, coolant is circulating.

DIAGNOSIS AND TESTING - COOLING SYSTEM
LEAK TESTING

WARNING: IF VEHICLE HAS BEEN RUN RECENTLY,
WAIT 15 MINUTES BEFORE REMOVING PRESSURE
CAP. PLACE A SHOP TOWEL OVER THE CAP, AND
WITHOUT PUSHING DOWN, ROTATE IT COUNTER-
CLOCKWISE TO THE FIRST STOP. ALLOW FLUIDS
TO ESCAPE THROUGH THE OVERFLOW TUBE.
WHEN THE SYSTEM STOPS PUSHING COOLANT
AND STEAM INTO THE COOLANT RECOVERY BOT-
TLE AND PRESSURE DROPS, PUSH DOWN ON THE
CAP AND REMOVE IT COMPLETELY. SQUEEZING
THE RADIATOR INLET HOSE WITH A SHOP TOWEL

(TO CHECK PRESSURE) BEFORE AND AFTER
TURNING TO THE FIRST STOP IS RECOMMENDED.

With engine not running, wipe the coolant filler

neck sealing seat clean. The radiator should be full.

Attach a cooling system pressure tester (Tool 7700

or equivalent) to the coolant filler neck, as shown in
(Fig. 2) and apply 104 kPa (15 psi) pressure. If the
pressure drops more than 2 psi in 2 minutes inspect
all points for external leaks.

All hoses, radiator and heater, should be moved

while at 104 kPa (15 psi) since some leaks occur
while driving due to engine rock, etc.

If there are no external leaks after the gauge dial

shows a drop in pressure, detach the tester. Start
engine and run the engine to normal operating tem-
perature in order to open the thermostat and allow
the coolant to expand. Reattach the tester. If the nee-
dle on the dial fluctuates, it indicates a combustion
leak and is usually a head gasket leak.

Fig. 2 Pressure Testing Cooling System—Typical

1 - PRESSURE TESTER

PL/SRT-4

ENGINE - 2.0L SOHC

7 - 17

ENGINE - 2.0L SOHC (Continued)

Content .. 62 63 64 65 ..