2013 JEEP GRAND CHEROKEE fuel pressure

Periodic Safety Checks You Should Make Outside
The Vehicle
Tires
Examine tires for excessive tread wear and uneven wear
patterns. Check for stones, nails, glass, or other objects
lodged in the tread or sidewall. Inspect the tread for cuts
and cracks. Inspect sidewalls for cuts, cracks and bulges.
Check the wheel nuts for tightness. Check the tires
(including spare) for proper cold inflation pressure.
Lights
Have someone observe the operation of brake lights and
exterior lights while you work the controls. Check turn
signal and high beam indicator lights on the instrument
panel.
Door Latches
Check for positive closing, latching, and locking.
Fluid Leaks
Check area under vehicle after overnight parking for fuel,
engine coolant, oil, or other fluid leaks. Also, if gasoline
fumes are detected or if fuel, power steering fluid, or
brake fluid leaks are suspected, the cause should be
located and corrected immediately.
116 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE

Accordingly, when the low tire pressure telltale illumi-
nates, you should stop and check your tires as soon as
possible, and inflate them to the proper pressure. Driving
on a significantly under-inflated tire causes the tire to
overheat and can lead to tire failure. Under-inflation also
reduces fuel efficiency and tire tread life, and may affect
the vehicle’s handling and stopping ability.
Please note that the TPMS is not a substitute for proper
tire maintenance, and it is the driver ’s responsibility to
maintain correct tire pressure, even if under-inflation has
not reached the level to trigger illumination of the TPMS
low tire pressure telltale.
Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the system is not
operating properly. The TPMS malfunction indicator is
combined with the low tire pressure telltale. When the
system detects a malfunction, the telltale will flash for
approximately one minute and then remain continuouslyilluminated. This sequence will continue upon subse-
quent vehicle start-ups as long as the malfunction exists.
When the malfunction indicator is illuminated, the sys-
tem may not be able to detect or signal low tire pressure
as intended. TPMS malfunctions may occur for a variety
of reasons, including the installation of replacement or
alternate tires or wheels on the vehicle that prevent the
TPMS from functioning properly. Always check the
TPMS malfunction telltale after replacing one or more
tires or wheels on your vehicle, to ensure that the
replacement or alternate tires and wheels allow the TPMS
to continue to function properly.
4
UNDERSTANDING YOUR INSTRUMENT PANEL 319

POWER STEERING .....................470
 FUEL SAVER TECHNOLOGY —
IF EQUIPPED ......................... .471
 PARKING BRAKE ..................... .471
 ELECTRONIC BRAKE CONTROL SYSTEM . . . .473
▫ Anti-Lock Brake System (ABS) ............474
▫ Traction Control System (TCS) ............474
▫ Brake Assist System (BAS) ...............475
▫ Electronic Roll Mitigation (ERM) ..........475
▫ Electronic Stability Control (ESC) ..........476
▫ Trailer Sway Control (TSC) ..............480
▫ ESC Activation/Malfunction Indicator Light
And ESC OFF Indicator Light ............481
TIRE SAFETY INFORMATION .............483
▫ Tire Markings ....................... .483
▫ Tire Identification Number (TIN) ...........487
▫ Tire Terminology And Definitions ..........488
▫ Tire Loading And Tire Pressure ...........489
 TIRES — GENERAL INFORMATION .........494
▫ Tire Pressure ....................... .494
▫ Tire Inflation Pressures .................495
▫ Tire Pressures For High Speed Operation . . . .496
▫ Radial Ply Tires ..................... .497
▫ All Season Tires – If Equipped ............497
▫
Summer Or Three Season Tires – If Equipped . . .498
444 STARTING AND OPERATING

▫Spare Tire Matching Original Equipped Tire
And Wheel – If Equipped ................498
▫ Compact Spare Tire – If Equipped .........499
▫ Full Size Spare – If Equipped .............499
▫ Limited-Use Spare – If Equipped ..........500
▫ Tire Spinning ....................... .500
▫ Tread Wear Indicators ..................501
▫ Life Of Tire ........................ .502
▫ Replacement Tires .....................502
 TIRE ROTATION RECOMMENDATIONS .....504

TIRE PRESSURE MONITOR SYSTEM (TPMS) . . .505
▫ Premium System – If Equipped ............508
▫ Tire Pressure Monitoring Low Pressure
Warnings .......................... .509▫
General Information ...................512
 FUEL REQUIREMENTS ..................513
▫ 6.4L Engine ......................... .513
▫ Reformulated Gasoline .................513
▫ Gasoline/Oxygenate Blends ..............514
▫ E-85 Usage In Non-Flex Fuel Vehicles .......514
▫ MMT In Gasoline .....................515
▫ Materials Added To Fuel ................515
▫ Fuel System Cautions ...................516
▫ Carbon Monoxide Warnings .............517
 ADDING FUEL ....................... .517
▫ Fuel Filler Cap (Gas Cap) ...............517
▫ Loose Fuel Filler Cap Message ............520
5
STARTING AND OPERATING 445

WARNING!(Continued)
•Unequal tire pressures from one side of the vehicle
to the other can cause the vehicle to drift to the
right or left.
• Always drive with each tire inflated to the recom-
mended cold tire inflation pressure.
Economy
Improper inflation pressures can cause uneven wear
patterns to develop across the tire tread. These abnormal
wear patterns will reduce tread life resulting in a need for
earlier tire replacement. Under-inflation also increases
tire rolling resistance resulting in higher fuel consump-
tion.
Ride Comfort And Vehicle Stability
Proper tire inflation contributes to a comfortable ride.
Over-inflation produces a jarring and uncomfortable
ride. Both under-inflation and over-inflation affect the stability of the vehicle and can produce a feeling of
sluggish response or over responsiveness in the steering.
Unequal tire pressures can cause erratic and unpredict-
able steering response.
Unequal tire pressure from side to side may cause the
vehicle to drift left or right.
Tire Inflation Pressures
The proper cold tire inflation pressure is listed on the
driver’s side “B” Pillar or rear edge of the driver’s side
door.
The tire pressure should be checked and adjusted as well
as inspected for signs of tire wear or visible damage at
least once a month. Use a good quality pocket-type gauge
to check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under-inflated.5
STARTING AND OPERATING 495

NOTE:
•The TPMS is not intended to replace normal tire care
and maintenance, or to provide warning of a tire
failure or condition.
• The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
• Driving on a significantly under-inflated tire causes
the tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling and
stopping ability.
• The TPMS is not a substitute for proper tire mainte-
nance, and it is the driver ’s responsibility to maintain
correct tire pressure using an accurate tire gauge, even
if under-inflation has not reached the level to trigger
illumination of the Tire Pressure Monitoring Telltale
Light. •
Seasonal temperature changes will affect tire pressure,
and the TPMS will monitor the actual tire pressure in
the tire.
Premium System – If Equipped
The Tire Pressure Monitor System (TPMS) uses wireless
technology with wheel rim-mounted electronic sensors to
monitor tire pressure levels. Sensors, mounted to each
wheel as part of the valve stem, transmit tire pressure
readings to the Receiver Module.
NOTE: It is particularly important, for you to regularly
check the tire pressure in all of your tires and to maintain
the proper pressure.
The Tire Pressure Monitor System (TPMS) consists of the
following components:
• Receiver Module
• Four Tire Pressure Monitoring Sensors
508 STARTING AND OPERATING

Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle,
springs, tires or wheels). Heavier axles or suspension
components sometimes specified by purchasers for in-
creased durability does not necessarily increase the vehi-
cle’s GVWR.
Tire Size
The tire size on the Vehicle Certification Label represents
the actual tire size on your vehicle. Replacement tires
must be equal to the load capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size
listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for
all loading conditions up to full GAWR.
Curb Weight
The curb weight of a vehicle is defined as the total weight
of the vehicle with all fluids, including vehicle fuel, at full
capacity conditions, and with no occupants or cargo
loaded into the vehicle. The front and rear curb weight
values are determined by weighing your vehicle on a
commercial scale before any occupants or cargo are
added.
Loading
The actual total weight and the weight of the front and
rear of your vehicle at the ground can best be determined
by weighing it when it is loaded and ready for operation.
The entire vehicle should first be weighed on a commer-
cial scale to insure that the GVWR has not been exceeded.
The weight on the front and rear of the vehicle should
then be determined separately to be sure that the load is
properly distributed over the front and rear axle. Weigh-
ing the vehicle may show that the GAWR of either the
522 STARTING AND OPERATING

CAUTION!(Continued)
•Your vehicle has been built with improved fluids
that protect the performance and durability of your
vehicle and also allow extended maintenance inter-
vals. Do not use chemical flushes in these compo-
nents as the chemicals can damage your engine,
transmission, power steering or air conditioning.
Such damage is not covered by the New Vehicle
Limited Warranty. If a flush is needed because of
component malfunction, use only the specified
fluid for the flushing procedure.
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. The best time to check the engine oil level is about five 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” range. Adding one quart of oil
when the reading is at the bottom of the “SAFE” range
will result in an oil level at the top of the “SAFE” range
on these engines.
NOTE:
Fill engine oil one quart at a time.
CAUTION!
•Overfilling or underfilling will cause oil aeration or
loss of oil pressure. This could damage your engine.
•Operating the engine with the oil levels below the
safe zone, or operating with oil levels that exceed the
top of the safe zone may cause engine damage.
564 MAINTAINING YOUR VEHICLE