engine JEEP WRANGLER 2006 Manual Online

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

Do not operate the engine with the tachometer
pointer in the red area. Engine damage will occur.
4

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.
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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.
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.

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.
Engine 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.

STARTING PROCEDURES
Before starting your vehicle, adjust your seat, adjust both
inside and outside mirrors, and fasten your seat belts.
WARNING!
Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build up may
cause serious injury or death.
You or others around you could be injured if you
attempt to start the engine with a manual transmis-
sion in gear — your vehicle will move. Remember,
always push the clutch pedal in fully and shift into
N (Neutral) before attempting to start the engine.

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.
Ignition Key Positions
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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.
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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.
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