2020 JEEP WRANGLER engine

STARTING THE ENGINE
Before starting your vehicle, adjust your seat,
adjust both inside and outside mirrors, and
fasten your seat belts.
WARNING!
• When exiting the vehicle, always remove
the key fob from the ignition and lock
your vehicle.
• Never leave children alone in a vehicle,
or with access to an unlocked vehicle.
• Allowing children to be in a vehicle un-
attended is dangerous for a number of
reasons. A child or others could be seri-
ously or fatally injured. Children should
be warned not to touch the parking
brake, brake pedal or the gear selector.
• Do not leave the key fob in or near the
vehicle, or in a location accessible to
children. A child could operate power
windows, other controls, or move the
vehicle.
• Do not leave children or animals inside
parked vehicles in hot weather. Interior
WARNING!
heat build-up may cause serious injury
or death.
Manual Transmission — If Equipped
Apply the parking brake, place the gear se-
lector in NEUTRAL, and press the clutch
pedal before starting the vehicle. This vehicle
is equipped with a clutch interlocking igni-
tion system. It will not start unless the clutch
pedal is pressed to the floor.
Four-Wheel Drive Models Only
In 4L mode, this vehicle will start regardless
of whether or not the clutch pedal is pressed
to the floor. This feature enhances off-road
performance by allowing the vehicle to start
when in 4L without having to press the clutch
pedal. The “4WD Low Indicator Light” will
illuminate when the transfer case has been
shifted into this mode.
Automatic Transmission — If Equipped
Start the vehicle with the gear selector in the
PARK position (vehicle can also be started in
NEUTRAL). Apply the brake before shifting
to any driving range.
Normal Starting — Gasoline Engine
NOTE:
Normal starting of either a cold or a warm
engine is obtained without pumping or press-
ing the accelerator pedal.
Cycle the ignition switch to the START posi-
tion and release when the engine starts. If the
engine fails to start within 10 seconds, cycle
the ignition switch to the LOCK/OFF position,
wait 10 to 15 seconds, then repeat the “Nor-
mal Starting” procedure.
Extreme Cold Weather (Below –22°F Or
−30°C)
To ensure reliable starting at these tempera-
tures, use of an externally powered electric
engine block heater (available from your au-
thorized dealer) is recommended.
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If Engine Fails To Start
WARNING!
• Never pour fuel or other flammable liq-
uid into the throttle body air inlet open-
ing in an attempt to start the vehicle.
This could result in flash fire causing
serious personal injury.
• Do not attempt to push or tow your
vehicle to get it started. Vehicles
equipped with an automatic transmis-
sion cannot be started this way. Un-
burned fuel could enter the catalytic
converter and once the engine has
started, ignite and damage the converter
and vehicle.
• If the vehicle has a discharged battery,
booster cables may be used to obtain a
start from a booster battery or the battery
in another vehicle. This type of start can
be dangerous if done improperly. Refer
to “Jump Starting Procedure” in “In
Case Of Emergency” for further informa-
tion.Without Tip Start — Manual Transmission Only
If the engine fails to start after you have
followed the “Normal Starting” or “Extreme
Cold Weather” procedures, it may be flooded.
Push the accelerator pedal all the way to the
floor and hold it there while cranking the
engine. This should clear any excess fuel in
case the engine is flooded.
CAUTION!
To prevent damage to the starter, do not
crank the engine for more than 15 seconds
at a time. Wait 10 to 15 seconds before
trying again.
If the engine has been flooded, it may start to
run, but not have enough power to continue
running when the key is released. If this
occurs, continue cranking with the accelera-
tor pedal pushed all the way to the floor.
Release the accelerator pedal and the key
once the engine is running smoothly.If the engine shows no sign of starting after
two 15-second periods of cranking with the
accelerator pedal held to the floor, repeat the
“Normal Starting” or “Extreme Cold
Weather” procedures.
With Tip Start — Automatic Transmission Only
If the engine fails to start after you have
followed the “Normal Starting” or “Extreme
Cold Weather” procedures, it may be flooded.
To clear any excess fuel, push the accelerator
pedal all the way to the floor and hold it.
Then, turn the ignition switch to the START
position and release it as soon as the starter
engages. The starter motor will disengage
automatically in 10 seconds. Once this oc-
curs, release the accelerator pedal, turn the
ignition switch to the LOCK position, wait
10 to 15 seconds, then repeat the “Normal
Starting” procedure.
CAUTION!
To prevent damage to the starter, wait
10 to 15 seconds before trying again.
STARTING AND OPERATING
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After Starting
The idle speed is controlled automatically,
and it will decrease as the engine warms up.
Normal Starting — Diesel Engine
1. The gear selector must be in the NEU-
TRAL or PARK position before you can
start the engine.
2. Turn the ignition key to the ON position.
3. Watch for the “Wait To Start Light” in the
instrument cluster. Refer to “Instrument
Cluster” in “Getting To Know Your Instru-
ment Panel” for further review. It will glow
for two to ten seconds or more, depending
on engine temperature. When the “Wait
To Start Light” goes out, the engine is
ready to start.
4. Tip Start Feature (Automatic Transmission
Only)
Do notpress the accelerator. Turn the
ignition key to the START position and
then release it. The starter motor will
continue to run, and it will automatically
disengage when the engine is running. If
the engine fails to start, the starter willdisengage automatically in 25 seconds.
If this occurs, turn the ignition switch to
the LOCK position, wait 25 to 30 sec-
onds, then repeat the “Normal Starting”
procedure.
NOTE:
The starter motor may run up to 30 sec-
onds in very cold conditions until the
engine is started. The starter can be dis-
engaged by turning the ignition key to
the OFF position, if required.
5. Without Tip Start Feature (Manual Trans-
mission Only)
Turn the ignition switch to the START
position and release when the engine
starts. If the engine fails to start within
10 seconds, turn the ignition switch to
the LOCK position, wait 10 to 15 sec-
onds, then repeat the “Normal Starting”
procedure.
6. After the engine starts, allow it to idle for
approximately 30 seconds before driving.
This allows oil to circulate and lubricate
the turbocharger.
Diesel Engine Warm-Up
Avoid full throttle operation when the engine
is cold. When starting a cold engine, bring the
engine up to operating speed slowly to allow
the oil pressure to stabilize as the engine
warms up.
NOTE:
High-speed, no-load running of a cold engine
can result in excessive white smoke and poor
engine performance. No-load engine speeds
should be kept under 1,200 rpm during the
warm-up period, especially in cold, ambient
temperature conditions.
If temperatures are below 32°F (0°C), oper-
ate the engine at moderate speeds for five
minutes before full loads are applied.
Diesel Engine Idling — In Cold Weather
Avoid prolonged idling in ambient tempera-
tures below 0°F (-18°C). Long periods of
idling may be harmful to your engine because
combustion chamber temperatures can drop
so low that the fuel may not burn completely.
Incomplete combustion allows carbon and
varnish to form on piston rings and injector
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nozzles. Also, the unburned fuel can enter
the crankcase, diluting the oil and causing
rapid wear to the engine.
Stopping the Engine
The following chart should be used as a guide
in determining the amount of engine idle
time required to sufficiently cool down the
turbocharger before shut down, depending
upon the type of driving and the amount of
cargo.Before turning off your turbo diesel engine,
always allow the engine to return to normal idle
speed and run for several seconds. This assures
proper lubrication of the turbocharger. This is
particularly necessary after any period of hard
driving.
Idle the engine a few minutes before routine
shutdown. After full load operation, idle the
engine three to five minutes before shutting itdown. This idle period will allow the lubricat-
ing oil and coolant to carry excess heat away
from the combustion chamber, bearings, in-
ternal components, and turbocharger. This is
especially important for turbocharged,
charge air cooled engines.
TURBOCHARGER "COOL DOWN" CHART
Driving
ConditionsLoad Turbocharger
TemperatureIdle Time (In Minutes)
Before Shut Down
Stop & Go Empty Cool Less than 1
Stop & Go Medium Warm 1
Highway Speeds Medium Warm 2
City Traffic Max. GCWR Warm 3
Highway Speeds Max. GCWR Warm 4
Uphill Grade Max. GCWR Hot 5
STARTING AND OPERATING
120

ENGINE BREAK-IN
RECOMMENDATIONS
A long break-in period is not required for the
engine and drivetrain (transmission and axle)
in your vehicle.
Drive moderately during the first 300 miles
(500 km). After the initial 60 miles
(100 km), speeds up to 50 or 55 mph (80 or
90 km/h) are desirable.
While cruising, brief full-throttle acceleration
within the limits of local traffic laws contrib-
utes to a good break-in. Wide-open throttle
acceleration in low gear can be detrimental
and should be avoided.
The engine oil installed in the engine at the
factory is a high-quality energy conserving
type lubricant. Oil changes should be consis-
tent with anticipated climate conditions un-
der which vehicle operations will occur. For
the recommended viscosity and quality
grades, refer to “Dealer Service” in “Servic-
ing And Maintenance”.
CAUTION!
Never use Non-Detergent Oil or Straight
Mineral Oil in the engine or damage may
result.
NOTE:
A new engine may consume some oil during
its first few thousand miles (kilometers) of
operation. This should be considered a nor-
mal part of the break-in and not interpreted
as a problem.
PARKING BRAKE
Before exiting the vehicle, make sure that the
parking brake is fully applied. Also, be cer-
tain to leave an automatic transmission in
PARK, or manual transmission in REVERSE
or FIRST gear.
The parking brake lever is located in the
center console. To apply the parking brake,
pull the lever up as firmly as possible. To
release the parking brake, pull the lever up
slightly, push the center button, then lower
the lever completely.When the parking brake is applied with the
ignition switch ON, the “Brake Warning Light”
in the instrument cluster will illuminate.
NOTE:
• When the parking brake is applied and the
automatic transmission is placed in gear,
the “Brake Warning Light” will flash. If
vehicle speed is detected, a chime will
sound to alert the driver. Fully release the
parking brake before attempting to move
the vehicle.
Parking Brake Lever
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Recommended Vehicle Shift Speeds
To utilize your manual transmission effi-
ciently for both fuel economy and perfor-
mance, it should be upshifted as listed inrecommended shift speed chart. Shift at the
vehicle speeds listed for acceleration. When
heavily loaded or pulling a trailer these rec-
ommended up-shift speeds may not apply.
Manual Transmission Shift Speeds in MPH (KM/H)
Engine Speeds 1 to 2 2 to 3 3 to 4 4 to 5 5 to 6
3.6LAccel. 15 (24) 24 (39) 34 (55) 47 (76) 56 (90)
Cruise 10 (16) 19 (31) 27 (43) 37 (60) 41 (66)
NOTE:
Vehicle speeds shown in the chart above are
for 2H and 4H only, vehicle speeds in 4L
would be significantly less.
Downshifting
Moving from a high gear down to a lower gear
is recommended to preserve brakes when
driving down steep hills. In addition, down-
shifting at the right time provides better ac-
celeration when you desire to resume speed.
Downshift progressively. Do not skip gears to
avoid overspeeding the engine and clutch.
WARNING!
Do not downshift for additional engine
braking on a slippery surface. The drive
wheels could lose their grip, and the ve-
hicle could skid.
CAUTION!
• Skipping gears and downshifting into
lower gears at higher vehicle speeds can
damage the engine and clutch systems,
Any attempt to shift into lower gear with
clutch pedal depressed may result dam-
age to the clutch system. Shifting into
CAUTION!
lower gear and releasing the clutch may
result in engine damage.
• When descending a hill, be very careful
to downshift one gear at a time to pre-
vent overspeeding the engine which can
cause engine damage, and/or clutch
damage, even if the clutch pedal is
pressed. If transfer case is in low range
the vehicle speeds to cause engine and
clutch damage are significantly lower.
• Failure to follow the maximum recom-
mended downshifting speeds may cause
the engine damage and/or damage the
STARTING AND OPERATING
124

CAUTION!
clutch, even if the clutch pedal is
pressed.
• Descending a hill in low range with
clutch pedal depressed could result in
clutch damage.
Maximum Recommended Downshift Speeds
CAUTION!
Failure to follow the maximum recom-
mended downshifting speeds may cause
the engine to overspeed and/or damage the
clutch disc, even if the clutch pedal is
pressed.
Manual Transmission Downshift Speeds in MPH (KM/H)
Gear Selection 6 to 5 5 to 4 4 to 3 3 to 2 2 to 1
Maximum Speed 80 (129) 70 (113) 50 (81) 30 (48) 15 (24)
NOTE:
Vehicle speeds shown in the chart above are
for 2H and 4H only, vehicle speeds in 4L
would be significantly less.Reverse Shifting
To shift into REVERSE, bring the vehicle to a
complete stop. Press the clutch and pause
briefly to allow the gear train to stop rotating.
Beginning from the NEUTRAL position, move
the gear selector in one quick, smooth motion
straight across and into the REVERSE area
(the driver will feel a firm “click” as the
shifter passes the “knock-over”). Complete
the shift by pulling the gear selector into
REVERSE.The “knock-over” provides a resistance to the
driver from accidentally entering the RE-
VERSE shift area and warns the driver that
they are about to shift the transmission into
REVERSE. Due to this feature, a slow shift to
REVERSE can be perceived as a high shift
effort.
125

AUTOMATIC
TRANSMISSION — IF
EQUIPPED
CAUTION!
Damage to the transmission may occur if
the following precautions are not ob-
served:
• Shift into or out of PARK or REVERSE
only after the vehicle has come to a
complete stop.
• Do not shift between PARK, REVERSE,
NEUTRAL, or DRIVE when the engine is
above idle speed.
• Before shifting into any gear, make sure
your foot is firmly pressing the brake
pedal.
NOTE:
You must press and hold the brake pedal
while shifting out of PARK.
WARNING!
•Never use the PARK position as a substi-
tute for the parking brake. Always apply
the parking brake fully when exiting the
vehicle to guard against vehicle move-
ment and possible injury or damage.
• Your vehicle could move and injure you
and others if it is not in PARK. Check by
trying to move the gear selector out of
PARK with the brake pedal released.
Make sure the transmission is in PARK
before exiting the vehicle.
• It is dangerous to shift out of PARK or
NEUTRAL if the engine speed is higher
than idle speed. If your foot is not firmly
pressing the brake pedal, the vehicle
could accelerate quickly forward or in
reverse. You could lose control of the
vehicle and hit someone or something.
Only shift into gear when the engine is
idling normally and your foot is firmly
pressing the brake pedal.
• Unintended movement of a vehicle
could injure those in or near the vehicle.
As with all vehicles, you should never
WARNING!
exit a vehicle while the engine is run-
ning. Before exiting a vehicle always
come to a complete stop, then apply the
parking brake, shift the transmission
into PARK, turn the engine OFF, and
remove the ignition key. Once the key is
removed, the transmission is locked in
PARK, securing the vehicle against un-
wanted movement.
• When exiting the vehicle, always remove
the ignition key from the vehicle and
lock the vehicle.
• Never leave children alone in a vehicle,
or with access to an unlocked vehicle.
Allowing children to be in a vehicle un-
attended is dangerous for a number of
reasons. A child or others could be seri-
ously or fatally injured. Children should
be warned not to touch the parking
brake, brake pedal or the transmission
gear selector.
• Do not leave the ignition key in or near
the vehicle (or in a location accessible to
children). A child could operate power
STARTING AND OPERATING
126