
CONDITION POSSIBLE CAUSE CORRECTION
10. 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.10. 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 radiator
cap is defective.1. Check condition of radiator cap
and seals. Refer to Radiator Cap in
this section. Replace as necessary.
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 Testing Cooling
System For Leaks in this section.
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 Coolant
Concentration Testing in this
section. Adjust glycol-to-water ratio
as required.
HOSE OR HOSES COLLAPSE
WHEN ENGINE IS COOLING1. Vacuum created in cooling
system on engine cool-down is not
being relieved through coolant
recovery/reserve container system.1. (a) Radiator cap relief valve
stuck. Refer to Radiator Cap in this
section. Replace as necessary.
(b) Hose between coolant
recovery/reserve container and
radiator is kinked. Repair as
necessary.
(c) Vent at coolant recovery/reserve
container is plugged. Clean vent
and 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 appropriate Powertrain
Diagnostic Procedures manual for
operation of the DRB scan tool.
Repair as necessary.
2. Check for low coolant level. 2. Repair as necessary.
7 - 10 COOLING SYSTEMPL
DIAGNOSIS AND TESTING (Continued)

the coolant to expand. Reattach the tester. If the nee-
dle on the dial fluctuates it indicates a combustion
leak, usually a head gasket leak.
WARNING: WITH THE PRESSURE TESTER IN
PLACE PRESSURE BUILDS UP QUICKLY. ANY
EXCESSIVE PRESSURE BUILD-UP DUE TO CON-
TINUOUS ENGINE OPERATION MUST BE
RELEASED TO A SAFE PRESSURE POINT. NEVER
PERMIT PRESSURE TO EXCEED 138 kPa (20 psi).
If the needle on the dial does not fluctuate, race
the engine a few times. If an abnormal amount of
coolant or steam is emitted from the tail pipe, it may
indicate a faulty head gasket, cracked engine block,
or cracked cylinder head.
There may be internal leaks, which can be deter-
mined by removing the oil dipstick. If water globules
appear intermixed with the oil, it indicates an inter-
nal leak in the engine. If there is an internal leak,
the engine must be disassembled for repair.
PRESSURE CAP TO FILLER NECK SEAL
PRESSURE RELIEF CHECK
The pressure cap upper gasket (seal) pressure
relief can be checked by removing the overflow hose
at the radiator filler neck nipple (Fig. 13). Attach the
radiator pressure tester to thefiller neck nipple,
and pump air into the system. The pressure cap
upper gasket should relieve pressure at 69-124 kPa
(10-18 psi), and hold pressure at 55 kPa (8 psi) min-
imum.
WARNING: THE WARNING WORDS DO NOT OPEN
HOT ON THE PRESSURE CAP IS A SAFETY PRE-
CAUTION. WHEN HOT, THE COOLING SYSTEM
BUILDS UP PRESSURE. TO PREVENT SCALDING
OR OTHER INJURY, THE PRESSURE CAP SHOULD
NOT BE REMOVED WHILE THE SYSTEM IS HOT
AND/OR UNDER PRESSURE.
There is no need to remove the pressure cap at any
timeexceptfor the following purposes:
²Check and adjust coolant freeze point
²Refill system with new coolant
²Conducting service procedures
²Checking for leaks
WARNING: IF VEHICLE HAS BEEN RUN RECENTLY,
WAIT 15 MINUTES BEFORE REMOVING CAP.
PLACE A SHOP TOWEL OVER THE CAP, AND WITH-
OUT PUSHING DOWN, ROTATE IT COUNTER-
CLOCKWISE TO THE FIRST STOP. ALLOW FLUIDSTO ESCAPE THROUGH THE OVERFLOW TUBE.
WHEN THE SYSTEM STOPS PUSHING COOLANT
AND STEAM INTO THE CRS TANK 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.
PRESSURE TESTING COOLING SYSTEM
PRESSURE CAP
Dip the pressure cap in water; clean off any depos-
its on the vent valve or its seat, and apply the cap to
end of radiator pressure tester (Fig. 14). Working the
plunger, increase the pressure to 104 kPa (15 psi) on
the gauge. If the pressure cap fails to hold pressure
of at least 97 kPa (14 psi), replace the cap.
Fig. 13 Cooling System Pressure Cap
1 ± PRESSURE RATING
2 ± FILLER NECK SEAL
3 ± PRESSURE VALVE
4 ± VACUUM VENT VALVE (SHOWN IN SEALING POSITION)
7 - 16 COOLING SYSTEMPL
DIAGNOSIS AND TESTING (Continued)

CAUTION: The radiator pressure tester is very sen-
sitive to small air leaks that will not cause cooling
system problems. A pressure cap that does not
have a history of coolant loss should not be
replaced just because it leaks slowly when tested
with this tool. Add water to the tool. Turn the tool
upside down, and recheck the pressure cap to con-
firm that the cap is faulty.
If the pressure cap tests properly while posi-
tioned the on radiator pressure tester, but will not
hold pressure or vacuum when positioned on the
filler neck, inspect the filler neck and cap top gas-
ket for irregularities that may prevent the cap from
sealing properly.
LOW COOLANT LEVEL AERATION
²Will cause corrosion in the system.
²High reading shown on the temperature gauge.
²Air in the coolant will also cause loss of flow
through the heater.
²Exhaust gas leaks into the coolant can also
cause the above problems.
DEAERATION
Air can only be removed from the system by gath-
ering under the pressure cap. On the next heat up it
will be pushed past the pressure cap into the coolant
recovery container by thermal expansion of the cool-
ant. It then escapes to the atmosphere in the coolant
recovery container and is replaced with coolant on
cool down.
TEMPERATURE GAUGE INDICATION
At idle the temperature gauge could rise slowly to
about 1/2 gauge travel. The fan will come on and the
gauge could drop to about 1/3 gauge travel, this is
normal.
ENGINE BLOCK HEATER
If heater unit does not operate (Fig. 15), possible
causes can be either the power cord or the heater ele-
ment. Test the power cord for continuity with a 110-
volt voltmeter or 110-volt test light. Test heater
element continuity with an ohmmeter or a 12-volt
test light.
CAUTION: To prevent damage, the power cord
must be secured in its retainer clips and away from
any components that may cause abrasion or dam-
age, such as linkages, exhaust components, etc.
SERVICE PROCEDURES
COOLANT LEVEL CHECKÐROUTINE
NOTE: Do not remove radiator cap for routine cool-
ant level inspections.
The coolant recovery/reserve system provides a
quick visual method for determining the coolant level
without removing the radiator cap. Simply observe,
with the engine idling and warmed up to normal
operating temperature, that the level of the coolant
in the recovery/reserve container (Fig. 16) is between
the FULL HOT and ADD marks.
Fig. 14 Pressure Testing Radiator Cap
1 ± PRESSURE CAP
2 ± PRESSURE TESTER
Fig. 15 Engine Block Heater
1 ± CORE PLUG
2 ± BLOCK HEATER
3 ± POWER CORD
PLCOOLING SYSTEM 7 - 17
DIAGNOSIS AND TESTING (Continued)

COOLING SYSTEMÐDRAINING
NOTE: Drain, flush, and fill the cooling system at
the mileage or time intervals specified in Group 0,
Lubrication and Maintenance. If the solution is dirty,
rusty, or contains a considerable amount of sedi-
ment; clean and flush with a reliable cooling system
cleaner. Care should be taken in disposing of the
used engine coolant from your vehicle. Check gov-
ernmental regulations for disposal of used engine
coolant.
Without removing radiator pressure cap and
with system not under pressure:
(1) Shut engine off and turn draincock counter-
clockwise to open (Fig. 18).
(2) The coolant reserve tank should empty first,
then remove the pressure cap. (if not, Refer to Test-
ing Cooling System for leaks).
COOLING SYSTEMÐREFILLING
First clean system to remove old glycol, see Cooling
System Cleaning.
Fill system with 50/50 glycol/water mix. Use anti-
freeze described in Coolant section.
Continue filling system until full, this provides bet-
ter heater performance.Be careful not to spill
coolant on drive belts or the generator.
Fill coolant reserve/recovery system to at least the
FULL HOT mark with 50/50 solution. It may be nec-
essary to add coolant to the reserve/recovery con-
tainer after three or four warm-up/cool down cycles
to maintain coolant level between the FULL HOT
and ADD marks; if any trapped air was removed
from the system.
REMOVAL AND INSTALLATION
WATER PUMP
REMOVAL
(1) Raise vehicle on a hoist. Remove right inner
splash shield.
(2) Remove accessory drive belts. Refer to proce-
dure in this section.
(3) Drain cooling system. Refer to Cooling System
Draining in this section.
(4) Remove power steering pump attaching bolts
and set pump and assembly aside. Power steering
lines do not need to be disconnected.
(5) Remove upper and lower torque isolator struts.
(6) Support engine from the bottom and remove
right engine mount attaching bolt.
(7) Remove right engine mount bracket.
(8) Remove timing belt and timing belt tensioner.
Refer to Group 9, Engine for procedures.
(9) Remove camshaft sprocket and rear timing belt
cover. Refer to Group 9, Engine for procedures.
(10) Remove water pump attaching screws to
engine and remove pump (Fig. 19).
INSTALLATION
(1) Apply MopartDielectric Grease to O-ring
before installation.
(2) Install new O-ring gasket in water pump body
O-ring groove (Fig. 20).
CAUTION: Make sure O-ring gasket is properly
seated in water pump groove before tightening
screws. An improperly located O-ring may cause
damage to the O-ring, resulting in a coolant leak.
(3) Assemble pump body to block and tighten
screws to 12 N´m (105 in. lbs.). Pressurize cooling
system to 15 psi with pressure tester and check
water pump shaft seal and O-ring for leaks.
Fig. 18 Cooling System Drain Cock Location
1 ± DRAIN COCKFig. 19 Water Pump
1 ± CYLINDER BLOCK
2 ± PUMP BODY
PLCOOLING SYSTEM 7 - 19
SERVICE PROCEDURES (Continued)

(4) Rotate pump by hand to check for freedom of
movement.
(5) Install rear timing belt cover and camshaft
sprocket.
(6) Install timing belt tensioner and timing belt.
Refer to Group 9, Engine for procedure.
(7) Install right engine mount bracket. Refer to
Group 9, Engine for procedure.
(8) Install upper and lower torque isolator struts.
Refer to Group 9, Engine for procedure.
(9) Fill cooling system. Refer to procedures in this
section.
(10) Install accessory drive belts. Refer to proce-
dure in this section.
(11) 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.
WATER PUMP INLET TUBE
The inlet tube connects the water pump to the
radiator and heater core. This tube is sealed by an
O-ring and held in place by fasteners to the block.
REMOVAL
CAUTION: Do not use any sharp tools to remove
hoses from inlet tube. This may cause the tube to
leak.
(1) Drain cooling system. Refer to procedure in
this section.
(2) Remove upper radiator hose to access the hose
connections at the inlet tube.(3) Remove intake manifold. Refer to Group 9,
Engine for procedure.
(4) Remove lower radiator hose and heater hose
from the inlet tube.
(5) Remove lower intake manifold support bracket.
(6) Remove the inlet tube to the block fasteners.
(7) Rotate tube while removing the tube from the
engine block (Fig. 21).
INSTALLATION
(1) Inspect the O-ring for damage before installing
the tube into the cylinder block (Fig. 21). Replace
O-ring as necessary.
(2) Lubricate O-ring with MopartDielectric
Grease and install inlet tube into the cylinder block
opening.
(3) Install inlet tube fasteners and tighten fasten-
ers to 12 N´m (105 in. lbs.).
(4) Install intake manifold lower support bracket
fasteners and tighten to 12 N´m (105 in. lbs.).
(5) Connect lower radiator hose and heater hose to
inlet tube.
(6) Install intake manifold. Refer to Group 9,
Engine for procedure.
(7) Install upper radiator hose.
(8) Fill cooling system. Refer to procedure in this
section.
(9) Pressure system to 104 kPa (15 psi) to check
for leaks.
ENGINE THERMOSTAT
REMOVAL
(1) Drain cooling system to the thermostat level or
below.
(2) Remove coolant recovery/reserve system hose
and upper radiator hose.
Fig. 20 Water Pump Body
1 ± IMPELLER
2 ± PUMP BODY
3 ± O-RING
Fig. 21 Water Pump Inlet Tube
1 ± O-RING
2 ± WATER PUMP INLET TUBE
FRONT
7 - 20 COOLING SYSTEMPL
REMOVAL AND INSTALLATION (Continued)

(3) Remove thermostat/engine outlet connector
bolts (Fig. 22).
(4) Remove thermostat and O-ring assembly.
INSTALLATION
(1) Clean all sealing surfaces.
(2) Place the new thermostat assembly into the
thermostat housing/outlet connector. Align vent with
notch in cylinder head.
(3) Install thermostat housing/outlet connector
onto cylinder head and tighten bolts to 12.5 N´m (110
in. lbs.).
(4) Install upper radiator hose.
(5) Connect the coolant recovery/reserve system
hose.
(6) Refill cooling system. Refer to procedure in this
section.
RADIATOR
REMOVAL
WARNING: DO NOT REMOVE THE CYLINDER
BLOCK PLUG OR THE RADIATOR DRAINCOCK
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM COOLANT CAN
OCCUR.
(1) Disconnect negative cable from battery.
(2) Drain cooling system. Refer to procedure in
this section.
(3) Remove upper radiator hose from the radiator.
(4) Disconnect and cap automatic transmission
hoses, if equipped.(5) Disconnect cooling fan motor electrical connec-
tor.
(6) Remove cooling fan module retaining screws,
located on the top of the shroud (Fig. 23). Lift shroud
up and out of bottom shroud attachment clips sepa-
rating shroud from radiator.
(7) Remove the lower radiator hose.
(8) Remove upper radiator isolator bracket mount-
ing screws (Fig. 24). Disconnect the engine block
heater wire, if equipped.
(9) Remove the air conditioning condenser attach-
ing screws located at the front of the radiator, if
equipped (Fig. 25), then lean condenser forward.
NOTE: It is not necessary to discharge the air con-
ditioning system to remove the radiator.
Fig. 22 Thermostat/Engine Outlet Connector
1 ± PRESSURE CAP
2 ± THERMOSTAT HOUSING/ENGINE OUTLET CONNECTOR
3 ± THERMOSTAT
4 ± O-RING
5 ± VENT FACING UP
Fig. 23 Fan Module Mounting
1 ± SCREWS
2 ± LOWER MOUNTS
3 ± FAN MOTOR ELECTRICAL CONNECTOR
Fig. 24 Radiator Mounting
1 ± UPPER RADIATOR HOSE
2 ± UPPER RADIATOR MOUNTS
PLCOOLING SYSTEM 7 - 21
REMOVAL AND INSTALLATION (Continued)

(10) Radiator can now be lifted free from engine
compartment.Care should be taken not to dam-
age radiator cooling fins or water tubes during
removal.
INSTALLATION
(1) Slide radiator down into position behind radia-
tor support (yoke).
(2) Attach air conditioning condenser to radiator, if
equipped (Fig. 25), with four mounting screws.
Tighten screws to 5.4 N´m (50 in. lbs.). Then seat the
radiator assembly lower rubber isolators into the
mounting holes provided in the lower crossmember.
(3) Install and tighten radiator isolator mounting
bracket screws to 10 N´m (90 in. lbs.) (Fig. 24). The
radiator should have clearance to move up, approxi-
mately 5±8 mm (0.20±0.31 in.) after assembled.
(4) Install lower radiator hose. Align the hose and
position the clamp so it will not interfere with engine
components.
(5) Connect automatic transmission hoses, if
equipped. Tighten hose clamps to 2 N´m (18 in. lbs.).
(6) Slide fan module down into clip(s) on lower
radiator flange (Fig. 23). Install retaining screws and
tighten to 7.5 N´m (65 in. lbs.).
(7) Connect the cooling fan motor electrical connec-
tor.
(8) Install upper radiator hose. Align the hose and
position the clamp so they will not interfere with the
engine or the hood.
(9) Connect negative cable to battery.
(10) Fill cooling system with coolant. Refer to pro-
cedure in this section.
(11) Operate engine until it reaches normal operat-
ing temperature. Check cooling system and auto-
matic transmission for correct fluid levels.
RADIATOR DRAINCOCK
REMOVAL
(1) Turn the drain cock stem counterclockwise to
unscrew the stem. When the stem is unscrewed to
the end of the threads, pull the stem (Fig. 26) from
the radiator tank.
INSTALLATION
(1) Push the draincock assembly body into the
tank opening.
(2) Tighten the draincock stem by turning clock-
wise to 2.0-2.7 N´m (18-25 in. lbs.).
COOLING FAN MODULE
All models use a single speed electric motor driven
cooling system fan. The fan module includes a motor,
fan blade, and support shroud. The module is fas-
tened to the radiator by screws.
REMOVAL
WARNING: DO NOT REMOVE THE CYLINDER
BLOCK PLUG OR THE RADIATOR DRAINCOCK
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM COOLANT CAN
OCCUR.
(1) Disconnect negative cable from battery.
(2) Drain cooling system below upper radiator hose
level. Refer to procedure in this section.
(3) Remove upper radiator hose from radiator (Fig.
27).
(4) Disconnect fan module electrical connector.
(5) Remove fan module screws from radiator (Fig.
28).
(6) Lift fan shroud up and out of lower shroud
attachment clips.
(7) Refer to Disassembly and Assembly in this sec-
tion for fan module sub-component service proce-
dures.
Fig. 25 A/C Condenser to Radiator Mounting Screws
1 ± AIR CONDITIONING CONDENSER TO RADIATOR
MOUNTING SCREWS
2 ± LOWER ISOLATOR MOUNTS
Fig. 26 Draincock
1 ± DRAIN COCK BODY
2 ± DRAIN COCK HOUSING
7 - 22 COOLING SYSTEMPL
REMOVAL AND INSTALLATION (Continued)

(2) Connect recovery hose to water outlet connec-
tor/thermostat housing (Fig. 29).
(3) Fill container to proper level. Refer to Cooling
System Refilling in this section.
ENGINE BLOCK HEATER
REMOVAL
(1) Drain coolant from radiator and cylinder block.
Refer to Cooling System Draining in this section for
procedure.
(2) Detach power cord plug from heater (Fig. 31).
(3) Loosen screw in center of heater. Remove
heater assembly (Fig. 31).
INSTALLATION
(1) Thoroughly clean core hole and heater seat.
(2) Insert heater assembly with element loop posi-
tionedupward (Fig. 31).
(3) With heater seated, tighten center screw
securely to assure a positive seal.
(4) Connect power cord to block heater (Fig. 31).
(5) Fill cooling system with coolant to the proper
level, vent air, and inspect for leaks.
ACCESSORY DRIVE BELTS
POWER STEERING PUMP AND AIR CONDITIONING
COMPRESSOR BELT
REMOVAL
(1) Using a 17 mm wrench, rotate belt tensioner
clockwise (Fig. 33) until belt can be removed from
power steering pump pulley. Gently, release spring
tension on tensioner.
(2) Remove belt (Fig. 34).
INSTALLATION
(1) Install belt (Fig. 34) over all pulleys except for
the power steering pump pulley.
(2) Using a 17 mm wrench, rotate belt tensioner
clockwise (Fig. 33) until belt can be installed onto
power steering pulley. Release spring tension onto
belt.
NOTE: When installing drive belt onto pulleys,
make sure that belt is properly routed and all
V-grooves make proper contact with pulley grooves.
(3) After belt is installed, inspect belt length indi-
cator marks (Fig. 35). The indicator mark should be
within the minimum belt length and maximum belt
length marks. On a new belt, the indicator mark
should align approximately with the nominal belt
length mark.
Fig. 31 Engine Block Heater
1 ± CORE PLUG
2 ± BLOCK HEATER
3 ± POWER CORD
Fig. 32 Accessory Drive Belts
1 ± GENERATOR BELT
2 ± AUTOMATIC BELT TENSIONER
3 ± POWER STEERING PUMP/A/C COMPRESSOR BELT
7 - 24 COOLING SYSTEMPL
REMOVAL AND INSTALLATION (Continued)