2010 JEEP WRANGLER engine

STARTING AND OPERATING
CONTENTS
Starting Procedures .................... 331
▫ Manual Transmission – If Equipped ....... 331
▫ Automatic Transmission – If Equipped ..... 331
▫ Normal Starting ..................... 331
▫ Extreme Cold Weather (Below –20°F Or
–29°C) ............................ 332
▫ If Engine Fails To Start ................ 332
▫ After Starting ....................... 334
 Engine Block Heater — If Equipped ........ 335
Manual Transmission — If Equipped ........ 335
▫ Shifting ........................... 336
▫ Downshifting ....................... 337
▫ Reverse Shifting ..................... 338
 Automatic Transmission — If Equipped ...... 339
▫ Key Ignition Park Interlock ............. 339
▫ Brake/Transmission Interlock System ...... 340
▫ Brake/Transmission Interlock Manual
Override .......................... 340
5

STARTING PROCEDURES
Before starting your vehicle, adjust your seat, adjust both
inside and outside mirrors, and fasten your seat belts.
WARNING!
Never leave children in the vehicle alone. Leaving
unintended children in a vehicle is dangerous for a
number of reasons. The child or others could be
seriously or fatally injured. The child could operate
power windows, other controls or move the vehicle.
Manual Transmission – If Equipped
Apply the parking brake, place the shift lever in NEU-
TRAL, and press the clutch pedal before starting the
vehicle. This vehicle is equipped with a clutch interlock-
ing ignition 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 Indicator Light” will illuminate when the
transfer case has been shifted into this mode.
Automatic Transmission – If Equipped
Start the vehicle with the shift lever in the PARK position
(vehicle can also be started in NEUTRAL). Apply the
brake before shifting to any driving range.
Normal Starting
NOTE:
Normal starting of either a cold or a warm
engine is obtained without pumping or pressing the
accelerator pedal.
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STARTING AND OPERATING 331

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 seconds, then repeat the “Normal
Starting” procedure.
Tip Start Feature – Automatic Transmission Only
Turn the ignition switch to the START position and
release it as soon as the starter engages. The starter motor
will continue to run, but will automatically disengage
itself when the engine is running. If the engine fails to
start, the starter will disengage automatically in 10 sec-
onds. If this occurs, turn the ignition switch to the LOCK
position, wait 10 to 15 seconds, then repeat the “Normal
Starting” procedure.
Extreme Cold Weather (below –20°F or –29°C)
To ensure reliable starting at these temperatures, use of
an externally-powered electric engine block heater (avail-
able from your authorized dealer) is recommended.
If Engine Fails to Start
WARNING!
•Never pour fuel or other flammable liquids into
the throttle body air inlet opening in an attempt to
start the vehicle. This could result in a flash fire
causing serious personal injury.(Continued)
332 STARTING AND OPERATING

WARNING! (Continued)
•Do not attempt to push or tow your vehicle to get
it started. Vehicles equipped with an automatic
transmission cannot be started this way. Unburned
fuel could enter the catalytic converter and, once
the engine has started, ignite and damage the
converter and vehicle. If the vehicle has a dis-
charged 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 dan-
gerous if done improperly. Refer to “Jump Start-
ing” in “What To Do In Emergencies” for further
information.Without Tip Start – Manual Transmission Only
If the engine fails to start after you have followed the
“Normal Starting” or “Extreme Cold Weather” proce-
dures, 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.5
STARTING AND OPERATING 333

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 accel-
erator 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 “Ex-
treme 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” proce-
dures, 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
occurs, 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 sec-
onds before trying again.
After Starting
The idle speed will automatically decrease as the engine
warms up.
334 STARTING AND OPERATING

ENGINE BLOCK HEATER — IF EQUIPPED
The engine block heater warms the engine, and permits
quicker starts in cold weather. Connect the cord to a
standard 110-115 Volt AC electrical outlet with a
grounded, three-wire extension cord. The engine block
heater cord is found under the hood bundled in front of
the battery tray.
WARNING!
Remember to disconnect the cord before driving.
Damage to the 110-115 Volt AC electrical cord could
cause electrocution.
Use the heater when temperatures below 0°F (-18°C) are
expected to last for several days.
MANUAL TRANSMISSION — IF EQUIPPED
WARNING!
You or others could be injured if you leave the
vehicle unattended without having the parking
brake fully applied. The parking brake should al-
ways be applied when the driver is not in the vehicle,
especially on an incline.
CAUTION!
Never drive with your foot resting on the clutch
pedal, or attempt to hold the vehicle on a hill with the
clutch pedal partially engaged, as this will cause
abnormal wear on the clutch.
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STARTING AND OPERATING 335

Manual Transmission Shift Speeds in MPH (KM/H)
En-
gine Speeds 1 to 2 2 to 3 3 to 4 4 to 5 5 to 6
3.8L Accel. 15 (24) 24 (39)34
(55) 47
(76) 56
(90)
Cruise 10 (16) 19 (31)27
(43) 37
(60) 41
(66)
Downshifting
Moving from a high gear down to a lower gear is
recommended to preserve brakes when driving down
steep hills. In addition, downshifting at the right time
provides better acceleration 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 vehicle could skid.
CAUTION!
When descending a hill, be very careful to downshift
one gear at a time to prevent overspeeding the engine
which can cause valve damage, and/or clutch disc
damage, even if the clutch pedal is pressed.
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STARTING AND OPERATING 337

Maximum Recommended Downshift Speeds
CAUTION!
Failure to follow the maximum recommended down-
shifting 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
Selec-
tion 6to5 5to4 4to3 3to2 2to1
Maxi-
mum
Speed 80 (129) 70 (113) 50 (81) 30 (48) 15 (24)
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 shift lever 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 shift
lever into REVERSE.
The “knock-over” prevents the driver from accidentally
entering the REVERSE shift area and warns the driver
that they are about to shift the transmission into RE-
VERSE. Due to this feature, a slow shift to REVERSE can
be perceived as a high shift effort.
338 STARTING AND OPERATING