2005 JEEP GRAND CHEROKEE fuel

DEALER SERVICE
Your dealer has the qualified service personnel, special
tools and equipment to perform all service operations in
an expert manner. Service Manuals are available which
include detailed service information for your vehicle.
Refer to these manuals before attempting any procedure
yourself.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
WARNING!
You can be badly injured working on or around a
motor vehicle. Do only that service work for which
you have the knowledge and the proper equipment. If
you have any doubt about your ability to perform a
service job, take your vehicle to a competent mechanic.
MAINTENANCE PROCEDURES
The pages that follow contain therequiredmaintenance
services determined by the engineers who designed your
vehicle.
Besides the maintenance items for which there are fixed
maintenance intervals, there are other items that should
operate satisfactorily without periodic maintenance.
However, if a malfunction of these items does occur, it
could adversely affect the engine or vehicle performance.
These items should be inspected if a malfunction is
observed or suspected.
Engine Oil
Checking Oil Level
To assure proper engine lubrication, the engine oil must
be maintained at the correct level. Check the oil level at
regular intervals, such as every fuel stop.
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The best time to check the engine oil level is about 5
minutes after a fully warmed engine is shut off or before
starting the engine after it has sat overnight.
Checking the oil while the vehicle is on level ground will
improve the accuracy of the oil level readings. Maintain
the oil level in the SAFE level range. Adding 1 U.S. Quart
(0.95L) of oil when the level is at the bottom of the SAFE
range will result in the level being at the top of the SAFE
range.
CAUTION!
Overfilling or underfilling the crankcase will cause
aeration or loss of oil pressure. This could damage
your engine.
Change Engine Oil
Road conditions as well as your kind of driving affect the
interval at which your oil should be changed. Check the
following to determine if any apply to you:
•Day or night temperatures are below 32°F (0°C)
•Stop and go driving
•Extensive engine idling
•Driving in dusty conditions
•Short trips of less than 10 miles (16.2 km)
•More than 50% of your driving is at sustained high
speeds during hot weather, above 90°F (32°C)
•Trailer towing
•Taxi, Police, or delivery service (Commercial Service)
•Off road or desert operation
•If equipped for and operating with E-85 (ethanol) fuel
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American Petroleum Institute (API) Engine Oil
Identification Symbol
This symbol means that the oil has
been certified by the American
Petroleum Institute (API). The
manufacturer only recommends
API Certified engine oils that
meet the requirements of
DaimlerChrysler Material Stan-
dard MS-6395. Use Moparor an
equivalent oil meeting the specifi-
cation MS-6395.
Engine Oil Viscosity (3.7L and 4.7L Engines)
SAE 5W-30 engine oil is recommended for all operating
temperatures. This engine oil improves low tempera-
ture starting and vehicle fuel economy. Refer to your
engine oil filler cap for the recommended engine oil
viscosity for your vehicle.
Engine Oil Viscosity (5.7L Engines)
SAE 5W-20 engine oil is recommended for all operating
temperatures. This engine oil improves low tempera-
ture starting and vehicle fuel economy. Refer to your
engine oil filler cap for the recommended engine oil
viscosity for your vehicle.
For information on engine oil filler cap location, see the
Engine Compartment illustration in this section.
Lubricants which do not have both, the engine oil certi-
fication mark and the correct SAE viscosity grade num-
ber should not be used.
NOTE:Vehicles equipped with 5.7L engines must use
5W–20 oil. Failure to do so may result in improper
operation of the Multiple Displacement System (MDS).
Refer to “Multi Displacement System” in Section 5 of this
manual.
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Special tools are required to properly measure tension
and to restore belt tension to factory specifications. Also,
check belt routing to make sure there is no interference
between the belts and other engine components.
Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New spark plugs should be
installed at the specified mileage. The entire set should be
replaced if there is any malfunction due to a faulty spark
plug. Refer to the “Vehicle Emission Control Informa-
tion” label in the engine compartment for spark plug
information.
Catalytic Converter
The catalytic converter requires the use of unleaded fuel
only. Leaded gasoline will destroy the effectiveness of the
converter as an emission control device.Under normal operating conditions, the catalytic con-
verter will not require maintenance. However, it is im-
portant to keep the engine properly tuned to assure
proper catalyst operation and prevent possible catalyst
damage.
CAUTION!
Damage to the catalytic converter can result if your
vehicle is not kept in proper operating condition. In
the event of engine malfunction, particularly involv-
ing engine misfire or other apparent loss of perfor-
mance, have your vehicle serviced promptly. Contin-
ued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and
vehicle.
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WARNING!
A hot exhaust system can start a fire if you park over
materials that can burn. Such materials might be
grass or leaves coming into contact with your ex-
haust system. Do not park or operate your vehicle in
areas where your exhaust system can contact any-
thing that can burn.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may suggest severe
and abnormal catalyst overheating. If this occurs, stop
the vehicle, turn off the engine and allow it to cool.
Service, including a tune up to manufacturer’s specifica-
tions, should be obtained immediately.
To minimize the possibility of catalytic converter dam-
age:
•Do not shut off the engine or interrupt the ignition
when the transmission is in gear and the vehicle is in
motion.
•Do not try to start the engine by pushing or towing the
vehicle.
•Do not idle the engine with any spark plug wires
disconnected or removed, such as when diagnostic
testing.
•Do not idle the engine for prolonged periods during
very rough idle or malfunctioning operating condi-
tions.
•Do not allow vehicle to run out of fuel.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
322 MAINTAINING YOUR VEHICLE

Ignition Cables
Replace the ignition cables (5.7L engines only) at the
mileage interval shown in the maintenance charts.
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.
Air Cleaner Filter
Under normal driving conditions, replace the air filter at
the intervals shown on “Maintenance Schedule A.” If,
however, you drive the vehicle frequently under dusty or
severe conditions, the filter element should be inspected
periodically and replaced if necessary at the intervals
shown on “Maintenance Schedule B.”
WARNING!
The air cleaner can provide protection in the case of
engine backfire. Do not remove the air cleaner
unless it is necessary for repair or maintenance.
Make sure that no one is near the engine compart-
ment before starting the vehicle with the air cleaner
removed. Failure to do so can result in serious
personal injury.
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7

If the belts need cleaning, use a mild soap solution or
lukewarm water. Do not remove the belts from the
vehicle to wash them.
Replace the belts if they appear frayed or worn or if the
buckles do not work properly.
Maintenance After Off-Pavement Driving
After extended operation in mud, sand or water, or
similar dirty conditions, have your brake discs, brake
linings, and axle joints inspected and cleaned as soon as
possible. This will prevent any abrasive material from
causing excessive wear or unpredictable braking action.
Following off-pavement usage, completely inspect the
underbody of your vehicle. Check tires, body structure,
steering, suspension and exhaust system for damage.
Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering and suspen-
sion. Retighten, if required, to torque values specified in
the Service Manual. Also check for accumulations ofvegetation or brush that could become a fire hazard, or
conceal damage to fuel lines, brake hoses, axle pinion
seals, and propeller shafts.
CAUTION!
Under frequent heavy-duty driving conditions,
change all lubricants and lubricate body compo-
nents, all driveline joints and steering linkage more
often than in normal service to prevent excessive
wear.
344 MAINTAINING YOUR VEHICLE

Cavity Fuse/Color Description
1 40 Amp Green HVAC Blower
2 30 Amp Pink Power Outlets
3 30 Amp Pink Rr Wiper/Ign R/O
4 30 Amp Pink ABS Pump
5 50 Amp Red Cabin Htr 1 (Diesel Only)
6 50 Amp Red ASD
7 30 Amp Pink Rr HVAC (XK)
8 40 Amp Green Acc Delay/Seats
9 Spare
10 40 Amp Green Starter/JB Power
11 30 Amp Pink Cig Ltr/T-Tow
12 40 Amp Green EBL/Htd Mirror
13 40 Amp Green JB Power
14 50 Amp Red Cabin Htr 2 (Diesel Only)
15 50 Amp Red Cabin Htr 3 (Diesel Only)
16 25 Amp Natural IPM/CoilsCavity Fuse/Color Description
17 Spare
18 20 Amp Yellow TCM/AC Clutch
19 20 Amp Yellow Ign Sw
20 20 Amp Yellow PCM Batt (Gasoline Only)
21 30 Amp Pink ABS Valves
22 Spare
23 20 Amp Yellow FDCM
24 20 Amp Yellow Fuel Pump
25 20 Amp Yellow FDCM/E-Diff.
26 15 Amp Blue Hyd/PCM (Diesel Only)
27 15 Amp Blue Brake/Stop Lamps
28 25 Amp Natural NGC/Injectors
29 Spare
30 Spare
31 Mini Relay Cabin Htr 1 Rly (Diesel
Only)
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