engine JEEP WRANGLER 2006 Workshop Manual

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, the “Normal Starting” or “Extreme Cold
Weather” procedures should be repeated.
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.
Long periods of engine idling, especially at high
engine speeds can cause excessive exhaust tempera-
tures which can damage your vehicle. Do not leave
your vehicle unattended with the engine running.

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
2.4L Accel. 14 (23) 24 (39) 34
(55) 46
(74) 57
(92)
Cruise 11 (18) 19 (31) 27
(43) 38
(61) 45
(72)
4.0L Accel. 15 (24) 24 (39) 34
(55) 47
(76) 56
(90)
Cruise 10 (16) 19 (31) 27
(43) 37
(60) 41
(66)
Clutch Interlocking Ignition System (Non —
Rubicon Models Only)
Manual transmission vehicles are equipped with a clutch
interlock safety feature. With this feature engaged, you
must depress the clutch pedal to allow cranking of the
engine. To temporarily bypass this safety feature while
off-road driving (4L range only), which will allow crank-
ing the engine without depressing the clutch, follow
these steps:
1. Locate the Power Distribution Center (PDC) in the
engine compartment. Refer to “Fuse Panel” in Section 7
of this manual. (See page 305 for more information.)
2. Put a 10 Amp fuse in the PDC cavity (#28) marked as
Clutch Override.
NOTE: A fuse is provided in fuseblock cavity (f19 or
f20) marked as Spare.
STARTING AND OPERATING 187
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It is dangerous to shift the selector lever out of “P” or
“N” if the engine speed is higher than idle speed. If
your foot is not firmly on the brake pedal, the
vehicle could accelerate quickly forward or in re-
verse. You could lose control of the vehicle and hit
someone or something. Only shift into gear when
the engine is idling normally and when your right
foot is firmly on the brake pedal.
Brake Transmission Shift Interlock System
This vehicle is equipped with a brake transmission shift
interlock system (BTSI) that holds the gearshift lever in
the P (Park) position when the ignition switch is in the
OFF position. To move the gear selector lever out of the
P (Park) position, the ignition switch must be turned to
the ON position, the brake pedal and the button on the
front of the shifter handle must be depressed.
Gear Ranges
P (Park)
Supplements the parking brake by locking the transmis-
sion. The engine can be started in this range. Never use P
(Park) while the vehicle is in motion. Apply the parking
brake when leaving the vehicle in this range. Always
apply the parking brake first, and then place the selector
in P (Park) position.
STARTING AND OPERATING 189
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WARNING!
Unintended movement of a vehicle could injure
those in and near the vehicle. As with all vehicles,
you should never exit a vehicle while the engine is
running. Before exiting a vehicle, you should always
shift the vehicle into P (Park), remove the key from
the ignition, and apply the parking brake. Once the
key is removed from the ignition, the transmission
shift lever is locked in the P (Park) position, securing
the vehicle against unwanted movement. Further-
more, you should never leave children unattended
inside a vehicle.
Before moving the shift lever out of P (Park), you
must turn the ignition from LOCK to ON so the
steering wheel and shift lever are released. Other-
wise, damage to the steering column or shifter could
result.

is coasting at 2 to 3 mph (3 to 5 km/h), shift the transfer
case lever firmly to the desired position. Do not pause in
transfer case N (Neutral).
NOTE: Pausing in transfer case N (Neutral) in vehicles
equipped with an automatic transmission may require
shutting the engine OFF to avoid gear clash while
completing the shift. If difficulty occurs, shift the auto-
matic transmission to N (Neutral), hold foot on brake,
and turn the engine OFF. Make shift to desired mode.
NOTE: Shifting into or out of 4L is possible with the
vehicle completely stopped, however, difficulty may oc-
cur due to the mating teeth not being properly aligned.
Several attempts may be required for clutch teeth align-
ment and shift completion to occur. The preferred
method is with the vehicle rolling at 2 to 3 mph (3 to 5
km/h). Avoid attempting to engage or disengage 4L with
the vehicle moving faster than 2 to 3 mph (3 to 5 km/h).WARNING!
Failure to engage a position completely can cause
transfer case damage or loss of power and vehicle
control. You could have an injury accident. Do not
drive the vehicle unless the transfer case is fully
engaged.

On vehicles equipped with a limited-slip differen-
tial, never run the engine with one rear wheel off the
ground. The vehicle may drive through the rear
wheel remaining on the ground and cause you to
lose control of your vehicle.5

WARNING!
To use your brakes and decelerate more safely, follow these tips:
•Do not “ride” the brakes by resting your foot on the pedal. This could
overheat the brakes and result in unpredictable braking action, longer
stopping distances, or brake damage.
•When descending mountains or hills, repeated braking can cause
brake fade with loss of braking control. Avoid repeated heavy braking
by downshifting the transmission whenever possible.
•Do not downshift on icy or slippery roads, because engine braking
may cause skidding and loss of control.
•Engines may idle at higher speeds during warm-up, which could
cause rear wheels to spin and result in loss of vehicle control. Be
especially careful while driving on slippery roads, in close-quarter
maneuvering, parking or stopping. Remember, always engage
4-wheel drive when driving on slippery roads.
•Do not drive too fast for road conditions, especially when roads are wet
or slushy. A wedge of water can build up between the tire tread and the
road. This hydroplaning action can cause loss of traction, braking
ability, and control. Under such conditions, engage 4-wheel drive.
•After going through deep water or a car wash, brakes may become
wet, resulting in poor performance and unpredictable braking action.
Dry the brakes by gentle, intermittent pedal action while driving at
very slow speeds.
WARNING!
The weight and position of cargo and passengers can change
the vehicle center of gravity and vehicle handling. To avoid
loss of control resulting in personal injury, follow these
guidelines:
•Always place cargo evenly on the cargo floor, and locate
heavier objects as low and as far forward as possible.
•Place as much cargo as possible in front of the rear axle. Too
much weight or improperly placed weight over or behind
the rear axle can cause the rear of the vehicle to sway.
•Do not pile luggage or cargo higher than the top of the
seatback. This could impair visibility or become a danger-
ous projectile in a sudden stop or collision.
•The rear cargo space is intended for load carrying purposes
only, not for passengers, who should sit in seats and use
seat belts.
•On hardtop models, do not drive with the lift glass up. On
fabric top models, do not drive with the rear window curtain
up unless the side curtains are also open. This will prevent
dangerous exhaust fumes from entering the vehicle.

To help avoid personal injury, follow these tips:
•Never reach through the steering wheel to operate
steering column controls. Injury to your hands or
loss of vehicle control may result.
•If the engine stalls or power assist fails due to a
malfunction, vehicle steering and braking will
require greater effort.Significant over or under-inflation of tires, or mixing
sizes of tires or wheels on the vehicle can lead to loss
of braking effectiveness.
5

If the engine stalls or you lose headway or cannot
make it to the top of a steep hill or grade, never
attempt to turn around. To do so may result in
tipping and rolling the vehicle. Always back care-
fully straight down a hill in R (Reverse) gear. Never
back down a hill in N (Neutral) using only the brake.
Remember, never drive diagonally across a hill-always
drive straight up or down.
If the wheels start to slip as you approach the crest of a
hill, ease off the accelerator and maintain headway by
turning the front wheels slowly left and right. This may
provide a fresh “bite” into the surface and will usually
provide traction to complete the climb.
Traction Downhill
Shift the transmission into a low gear and the transfer
case to 4L (Low) range. Let the vehicle go slowly down
the hill with all four wheels turning against engine
compression drag. This will permit you to control the
vehicle speed and direction.
When descending mountains or hills, repeated braking
can cause brake fade with loss of braking control. Avoid
repeated heavy braking by downshifting the transmis-
sion whenever possible.
STARTING AND OPERATING 211
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It is necessary to follow these steps to be certain that
the transfer case is fully in N (Neutral) before
recreational towing to prevent damage to internal
parts.
Damage to the transmission may occur if the trans-
mission is shifted into P (Park) with the transfer case
in N (Neutral) and the engine running. With the
transfer case in N (Neutral) ensure that the engine is
off prior to shifting the transmission into P (Park)
(refer to step s7–8above).
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