engine JEEP WRANGLER 2007 JK / 3.G Repair Manual

4. Start engine.
5. Shift automatic transmission into D (Drive) or manual
transmission into gear.
6. Release brake pedal and ensure that there is no vehicle
movement.
7. Shut the engine off and place the ignition key into the
ACC position.
8. Shift automatic transmission into P (Park).
9. Apply parking brake.
10. Attach vehicle to the tow vehicle with tow bar.
11. Release parking brake.
12. Disconnect the negative battery cable, and secure it
away from the negative battery post.CAUTION!
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 steps 7 – 8 above).
Shifting Out Of Neutral (N)
Use the following procedure to prepare your vehicle for
normal usage.
1. Shift automatic transmission into N (Neutral) or de-
press clutch pedal on manual transmission.
2. Shift transfer case lever into desired position.
STARTING AND OPERATING 347
5

3. Shift automatic transmission into D (Drive) or release
clutch on manual transmissions.
NOTE:When shifting out of transfer case N (Neutral)
on automatic transmission equipped vehicles, turning
the engine off may be required to avoid gear clash.
WARNING!
You or others could be injured if you leave the
vehicle unattended with the transfer case in the N
(Neutral) position without first fully engaging the
parking brake. The transfer case N (Neutral) position
disengages both the front and rear driveshafts from
the powertrain and will allow the vehicle to move
despite the transmission position. The parking brake
should always be applied when the driver is not in
the vehicle.
CAUTION!
•Do not use a bumper mounted clamp-on tow bar
on your vehicle. The bumper face bar will be
damaged.
348 STARTING AND OPERATING

WHAT TO DO IN EMERGENCIES
CONTENTS
Hazard Warning Flashers.................350
If Your Engine Overheats.................351
Jacking And Tire Changing................352
▫Jack Location........................352
▫Spare Tire Stowage....................353▫Preparations For Jacking................353
▫Jacking Instructions....................354
Jump Starting.........................356
Emergency Tow Hooks — If Equipped........358
Towing A Disabled Vehicle................359
6

IF YOUR ENGINE OVERHEATS
In any of the following situations, you can reduce the
potential for overheating by taking the appropriate ac-
tion.
•On the highways — Slow down.
•In city traffic — While stopped, put transmission in N
(Neutral), but do not increase engine idle speed.
NOTE:There are steps that you can take to slow down
an impending overheat condition. If your air conditioner
is on, turn it off. The air conditioning system adds heat to
the engine cooling system and turning off the A/C
removes this heat. You can also turn the Temperature
Control to maximum heat, the Mode Control to floor, and
the Fan Control to High. This allows the heater core to act
as a supplement to the radiator and aids in removing heat
from the engine cooling system.
CAUTION!
Driving with a hot cooling system could damage
your vehicle. If the temperature gauge reads “H”,
pull over and stop the vehicle. Idle the vehicle with
the air conditioner turned off until the pointer drops
back into the normal range. If the pointer remains on
the “H”, and you hear continuous chimes, turn the
engine off immediately, and call for service.
WHAT TO DO IN EMERGENCIES 351
6

WARNING!
Do not permit vehicles to touch each other as this
could establish a ground connection and personal
injury could result.
5. Connect the other cable, first to the negative terminal
of the booster battery and then to the engine of the
vehicle with the discharged battery. Make sure you have
a good contact on the engine.
WARNING!
•You should not try to start your vehicle by pushing
or towing.
•Do not connect the cable to the negative post of the
discharge battery. The resulting electrical spark
could cause the battery to explode.
•During cold weather when temperatures are be-
low freezing point, electrolyte in a discharged
battery may freeze. Do not attempt jump starting
because the battery could rupture or explode. The
battery temperature must be brought up above
freezing point before attempting jump start.
WHAT TO DO IN EMERGENCIES 357
6

6. Start the engine in the vehicle which has the booster
battery, let the engine idle a few minutes, then start the
engine in the vehicle with the discharged battery.
7. When removing the jumper cables, reverse the above
sequence exactly. Be careful of the moving belts and fan.
WARNING!
Any procedure other than above could result in:
1. Personal injury caused by electrolyte squirting out
the battery vent;
2. Personal injury or property damage due to battery
explosion;
3. Damage to charging system of booster vehicle or
of immobilized vehicle.
EMERGENCY TOW HOOKS — IF EQUIPPED
If your vehicle is equipped with tow hooks, they are
mounted in the front and the rear.
CAUTION!
Tow hooks are for emergency use only, to rescue a
vehicle stranded off road. Do not use tow hooks for
tow truck hookup or highway towing. You could
damage your vehicle. Tow straps are recommended
when towing the vehicle, chains may cause vehicle
damage.
358 WHAT TO DO IN EMERGENCIES

MAINTAINING YOUR VEHICLE
CONTENTS
Engine Compartment – 3.8L...............364
Onboard Diagnostic System — OBD II........365
▫Loose Fuel Filler Cap Message............366
Emissions Inspection And Maintenance
Programs............................366
Replacement Parts......................368
Dealer Service.........................368
Maintenance Procedures..................369
▫Engine Oil..........................369▫Drive Belts — Check Condition And Tension . . 372
▫Spark Plugs.........................373
▫Catalytic Converter....................373
▫Crankcase Emission Control System........375
▫Fuel Filter..........................375
▫Engine Air Cleaner Filter................375
▫Maintenance-Free Battery................376
▫Air Conditioner Maintenance.............376
▫Power Steering Fluid Check..............377
7

Fluid Capacities........................412
Fluids, Lubricants And Genuine Parts........413▫Engine.............................413
▫Chassis............................414
MAINTAINING YOUR VEHICLE 363
7

ENGINE COMPARTMENT – 3.8L
364 MAINTAINING YOUR VEHICLE

ONBOARD DIAGNOSTIC SYSTEM — OBD II
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBD II. This system monitors
the performance of the emissions, engine, and automatic
transmission control systems. When these systems are
operating properly, your vehicle will provide excellent
performance and fuel economy, as well as engine emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the “Malfunction Indicator Light.” It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be drivable and not
need towing, see your dealer for service as soon as
possible.CAUTION!
•Prolonged driving with the “Malfunction Indica-
tor Light” on could cause further damage to the
emission control system. It could also affect fuel
economy and driveability. The vehicle must be
serviced before any emissions tests can be per-
formed.
•If the “Malfunction Indicator Light” is flashing
while the engine is running, severe catalytic con-
verter damage and power loss will soon occur.
Immediate service is required.
MAINTAINING YOUR VEHICLE 365
7