2004 JEEP GRAND CHEROKEE check engine

To minimize the possibility of catalytic converter dam-
age:
²Do not shut off the engine or interrupt the ignition
when the transmission is in gear and the vehicle is in
motion.
²Do not try to start the engine by pushing or towing the
vehicle.
²Do not idle the engine with any spark plug wires
disconnected or removed, such as when diagnostic
testing.
²Do not idle the engine for prolonged periods during
very rough idle or malfunctioning operating condi-
tions.
²Do not allow vehicle to run out of fuel.NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
Crankcase Emission Control System
Proper operation of this system depends on freedom
from sticking or plugging due to deposits. As vehicle
mileage builds up, the PCV valve and passages may
accumulate deposits. If a valve is not working properly,
replace it with a new valve. DO NOT ATTEMPT TO
CLEAN THE OLD PCV VALVE!
Check ventilation hose for indication of damage or
plugging deposits. Replace if necessary.
Fuel Filter
A plugged fuel filter can cause hard starting or limit the
speed at which a vehicle can be driven. Should an
excessive amount of dirt accumulate in the fuel tank,
frequent replacement of the fuel filter which is mounted
in the fuel tank may be necessary.
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apparent, and/or the system is not functioning as antici-
pated. Coordinate inspection efforts through a certified
ªDaimlerChrysler Dealership.º
WARNING!
Fluid level should be checked on a level surface with
the engine off to prevent injury from moving parts,
and to insure accurate fluid level reading. Do not
overfill. Use only the manufacturer's recommended
fluid.
If necessary, add fluid to restore to the proper indicated
level. With a clean cloth, wipe any spilled fluid from all
surfaces. Refer to Recommended Fluids, Lubricants, and
Genuine Parts for correct fluid type.
Driveline And Steering Component Lubrication
U-joints (cardan joints) are sealed and do not require
lubrication. Prop shafts, yokes, ball joints and other
driveline and steering components may be provided with
grease fittings for lubrication. Lubrication of these com-
ponents at the intervals specified in the appropriate
ªMaintenance Scheduleº in Section 8 is very important,
particularly if your vehicle is subjected to off-road or
other heavy-duty use. See your authorized dealer for
complete service information.
Body Lubrication
Locks and all body pivot points, including such items as
seat tracks, doors, tailgate and hood hinges, should be
lubricated periodically to assure quiet, easy operation
and to protect against rust and wear. Prior to the appli-
cation of any lubricant, the parts concerned should be
wiped clean to remove dust and grit; after lubricating
excess oil and grease should be removed. Particular
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attention should also be given to hood latching compo-
nents to insure proper function. When performing other
underhood services, the hood latch, release mechanism
and safety catch should be cleaned and lubricated.
The external lock cylinders should be lubricated twice a
year, preferably in the fall and spring. Apply a small
amount of a high quality lubricant such as MopartLock
Cylinder Lubricant directly into the lock cylinder.
Windshield Wiper Blades
The rubber edges of the wiper blades and the windshield
should be cleaned periodically with a sponge or soft cloth
and a mild nonabrasive cleaner to remove accumulations
of salt or road film.
Operation of the wipers on dry glass for long periods
may cause deterioration of the wiper blades. Always use
washer fluid when using the wipers to remove salt or dirt
from a dry windshield.Avoid using the wiper blades to wipe frost or ice from the
windshield. Keep the blade rubber out of contact with
petroleum products such as engine oil, gasoline, etc.
Windshield Washers Ð Front and Rear
On vehicles equipped with a Vehicle Information Center,
the low washer fluid level will be indicated. When the
sensor detects a low fluid level, the windshield will light
on the vehicle graphic outline and the ªWasher Fluid
Lowº message will be displayed.
The fluid reservoir for the windshield washers and the
rear window washer is shared. It is located in the front of
the engine compartment on the passenger side and
should be checked for fluid level at regular intervals. Fill
the reservoir with windshield washer solvent (not radia-
tor antifreeze) and operate the system for a few seconds
to flush out the residual water.
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WARNING!
Commercially available windshield washer solvents
are flammable. They could ignite and burn you. Care
must be exercised when filling or working around
the washer solution.
Exhaust System
The best protection against carbon monoxide entry into
the vehicle body is a properly maintained engine exhaust
system.
If you notice a change in the sound of the exhaust system;
or if the exhaust fumes can be detected inside the vehicle;
or when the underside or rear of the vehicle is damaged;
have an authorized technician inspect the complete ex-
haust system and adjacent body areas for broken, dam-
aged, deteriorated, or mispositioned parts. Open seams
or loose connections could permit exhaust fumes to seepinto the passenger compartment. In addition, inspect the
exhaust system each time the vehicle is raised for lubri-
cation or oil change. Replace as required.
Cooling System
WARNING!
You or others can be badly burned by hot coolant or
steam from your radiator. If you see or hear steam
coming from under the hood, don't open the hood
until the radiator has had time to cool. Never try to
open a cooling system pressure cap when the radia-
tor or coolant bottle is hot.
Coolant Checks
Check coolant protection every 12 months (before the
onset of freezing weather, where applicable). If coolant is
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dirty or rusty in appearance, the system should be
drained, flushed and refilled with fresh coolant.
Check the front of the radiator for any accumulation of
bugs, leaves, etc. Clean the radiator by gently spraying
water from a garden hose at the back of the core.
Check the engine cooling system hoses for condition and
tightness of connection. Inspect the entire system for
leaks. Any hoses that show cuts or severe abrasion must
be replaced.
Cooling System Ð Drain, Flush, And Refill
At the intervals shown in the appropriate ªMaintenance
Schedule,º the system should be drained, flushed, and
refilled.
If the solution is dirty and contains a considerable
amount of sediment, clean and flush with reliable cooling
system cleaner. Follow with a thorough rinsing to remove
all deposits and chemicals.
Engine Coolant Disposal
Used ethylene glycol-based engine coolant is a regulated
substance requiring proper disposal. Check with your
local authorities to determine the disposal rules for your
community. Do not store ethylene glycol-based engine
coolant in open containers or allow it to remain in
puddles on the ground. Prevent ingestion by animals and
children. If ingested by a child, contact a physician
immediately. Clean up any ground spills immediately.
Selection Of Coolant
Use only the manufacturer's recommended coolant, refer
to Recommended Fluids, Lubricants, and Genuine Parts
for correct coolant type.
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Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of
coolant, and to insure that coolant will return to the
radiator from the coolant reserve tank.
The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
WARNING!
The warning words DO NOT OPEN HOT on the
cooling system pressure cap are a safety precaution.
Never add coolant when the engine is overheated.
Do not loosen or remove the cap to cool an over-
heated engine. Heat causes pressure to build up in
the cooling system. To prevent scalding or injury, do
not remove the pressure cap while the system is hot
or under pressure.
Coolant Level
Check the coolant level at least once a month or more
often in hot weather. Check the level when the engine is
at normal operating temperature. Check the coolant level
only in the coolant recovery bottle. The coolant level
must be between the FULL and the ADD mark on the
bottle.
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See your authorized dealer if the coolant level drops
quickly.
Points To Remember
NOTE:When the vehicle is stopped after a few miles of
operation, you may observe vapor coming from the front
of the engine compartment. This is normally a result of
moisture from rain, snow, or high humidity accumulat-
ing on the radiator and being vaporized when the
thermostat opens, allowing hot coolant to enter the
radiator.
If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.
²Do not overfill the coolant bottle.
²Check coolant freeze point in the system.
²If frequent coolant additions are required, or if the
level in the recovery bottle does not drop when the
engine cools, the cooling system should be pressure
tested for leaks.
²Maintain coolant concentration at 50% ethylene glycol
antifreeze (minimum) in water for proper corrosion
protection of your engine that contains aluminum
components.
²Make sure that the radiator and coolant bottle hoses
are not kinked or obstructed.
²Do not change the thermostat for summer or winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory cooling performance, poor gas
mileage, and increased emissions.
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WARNING!
Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts and the
brake fluid catching fire.
Use only brake fluid that has been in a tightly closed
container to avoid contamination from foreign matter. Do
not allow petroleum base fluid to contaminate the brake
fluid as seal damage will result.
Automatic Transmission
Selection of Lubricant
It is important that the proper lubricant is used in the
transmission to assure optimum transmission perfor-
mance. Use only manufacturer's recommended transmis-
sion fluid, refer to Recommended Fluids, Lubricants, andGenuine Parts for correct fluid type. It is important that
the transmission fluid be maintained at the prescribed
level using the recommended fluid.
CAUTION!
Using a transmission fluid other than the manufac-
turer's recommended fluid may cause deterioration
in transmission shift quality and/or torque converter
shudder. Using a transmission fluid other than the
manufacturer's recommended fluid will result in
more frequent fluid and filter changes. Refer to
Recommended Fluids, Lubricants, and Genuine
Parts for correct fluid type.
Fluid Level Check ± 4.0L Engines (42RE)
This fluid level should be checked when the engine is
fully warmed up and the fluid in the transmission is
heated to its normal operating temperature. Operation of
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