2008 JEEP WRANGLER catalytic converter

2. Fully depress the accelerator pedal slowly three
times within 10 seconds.
3. Turn the ignition switch to the OFF/LOCK position.
NOTE: If the indicator message illuminates when you
start the vehicle, the oil change indicator system did not
reset. If necessary repeat this procedure.
25. Malfunction Indicator Light This light is a part of an Onboard Diagnostic
System called OBD II that monitors engine and
automatic transmission control systems. The light
will illuminate when the ignition is in the ON position
before engine start. If the bulb does not come on when
turning the key from OFF to ON, have the condition
checked promptly.
Certain conditions such as a loose or missing gas cap,
poor quality fuel, etc. may illuminate the light after
engine start. The vehicle should be serviced if the light stays on through several typical driving styles. In most
situations, the vehicle will drive normally and will not
require towing.
When the engine is running, the Malfunction Indicator
Light may flash to alert serious conditions that could lead
to immediate loss of power or severe catalytic converter
damage. The vehicle should be serviced as soon as
possible if this occurs.
26. Electronic Stability Program (ESP) Indicator
Light/Traction Control System (TCS) Indicator Light
This indicator light starts to flash as soon as the
tires lose traction and the ESP system becomes
active. The ESP/TCS Indicator Light also
flashes when TCS is active. If the ESP/TCS
Indicator Light begins to flash during acceleration, ease
up on the accelerator and apply as little throttle as
possible. Be sure to adapt your speed and driving to the
prevailing road conditions. The ESP/TCS Indicator Light
UNDERSTANDING YOUR INSTRUMENT PANEL 213
4

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.
• 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 Section 6 of
this manual for proper jump starting procedures
and follow them carefully.
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.
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.
STARTING AND OPERATING 273
5

It is even more important to look for gasoline without
MMT in Canada, because MMT can be used at levels
higher than those allowed in the United States.
MMT is prohibited in Federal and California-
reformulated gasoline.
Materials Added To Fuel
All gasoline sold in the United States is required to
contain effective detergent additives. Use of additional
detergents or other additives are not needed under
normal conditions and would result in additional cost.
Therefore you should not have to add anything to the
fuel.
Fuel System Cautions
CAUTION!
Follow these guidelines to maintain your vehicle’s
performance:
•The use of leaded gasoline is prohibited by Federal
law. Using leaded gasoline can impair engine perfor-
mance, and damage the emission control system.
•An out-of-tune engine, or certain fuel or ignition
malfunctions, can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune or
malfunctioning and may require immediate service.
Contact your authorized dealer for service assistance.
338 STARTING AND OPERATING

MAINTAINING YOUR VEHICLE
CONTENTS
Engine Compartment – 3.8L ...............378
 Onboard Diagnostic System — OBD II ........379
▫ Loose Fuel Filler Cap Message ............380
 Emissions Inspection And Maintenance
Programs ............................380
 Replacement Parts ......................382
 Authorized Dealer Service ................382
 Maintenance Procedures ..................383
▫ Engine Oil ..........................383 ▫
Drive Belts — Check Condition And Tension . . 386
▫ Spark Plugs .........................386
▫ Catalytic Converter ....................386
▫ Crankcase Emission Control System ........388
▫ Fuel Filter ..........................388
▫ Engine Air Cleaner Filter ................389
▫ Maintenance-Free Battery ................389
▫ Air Conditioner Maintenance .............390
▫ Power Steering Fluid Check ..............391
7

Drive Belts — Check Condition and Tension
Belt tension is controlled by means of an automatic
tensioner. No belt tension adjustments are required.
However, belt and belt tensioner condition should be
inspected at the specified intervals, and replaced if re-
quired. See your authorized dealer for service
At the mileage indicated in the Maintenance Schedule,
the condition of all the belts and tensioner should be
checked. Refer to Section 8 of this manual. Improper belt
tension can cause belt slippage and failure.
Belts should be inspected for evidence of cuts, cracks,
glazing, or frayed cords and replaced if there is indication
of damage, which could result in belt failure. Low
generator belt tension can cause battery failure.
Also, check belt routing to make sure there is no inter-
ference between the belts and other engine components.
Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New plugs should be in-
stalled at the mileage specified in the Maintenance Sched-
ule. Refer to Section 8 of this manual. The entire set
should be replaced if there is any malfunction due to a
faulty spark plug. Refer to Fluids, Lubricants, and Genu-
ine Parts in this section for spark plug information.
Catalytic Converter
The catalytic converter requires the use of unleaded fuel
only. Leaded gasoline will destroy the effectiveness of the
converter as an emission control device.
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.
386 MAINTAINING YOUR VEHICLE

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 exhaust
system. Do not park or operate your vehicle in areas
where your exhaust system can contact anything that
can burn.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may suggest severe
and abnormal catalyst overheating. If this occurs, stop
the vehicle, turn off the engine and allow it to cool.
Service, including a tune up to manufacturer’s specifica-
tions, should be obtained immediately.
MAINTAINING YOUR VEHICLE 387
7

To minimize the possibility of catalytic converter dam-
age:
•Do not shut off the engine or interrupt the ignition
when the transmission is in gear and the vehicle is in
motion.
•Do not try to start the engine by pushing or towing the
vehicle.
•Do not idle the engine with any spark plug wires
disconnected or removed, such as when diagnostic
testing.
•Do not idle the engine for prolonged periods during
very rough idle or malfunctioning operating condi-
tions.
•Do not allow vehicle to run out of fuel.NOTE:
Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
Crankcase Emission Control System
Proper operation of this system depends on freedom
from sticking or plugging due to deposits. As vehicle
mileage builds up, the PCV valve and passages may
accumulate deposits. If a valve is not working properly,
replace it with a new valve. DO NOT ATTEMPT TO
CLEAN THE OLD PCV VALVE!
Check ventilation hose for indication of damage or
plugging deposits. Replace if necessary.
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.
388 MAINTAINING YOUR VEHICLE

Axle Lock.......................... 290,291
Battery ............................... 389
Emergency Starting ..................... 371
Keyless Transmitter Replacement (RKE) ....... 24
Belts, Drive ............................ 386
Belts, Seat .............................. 41
Body Mechanism Lubrication ............... 392
Brake Assist System ...................... 107
Brake Assist Warning Light ................. 214
Brake Control System, Electronic ............. 105
Brake System ........................... 399
Anti-Lock (ABS) .................... 105,309
Hoses .............................. 400
Master Cylinder ....................... 400
Parking ............................. 308
Warning Light ........................ 207
Brake/Transmission Interlock ............... 281
Break-In Recommendations, New Vehicle ........ 75Bulb Replacement
....................... 420
Capacities, Fluid ........................ 424
Caps, Filler Fuel ................................ 340
Power Steering ........................ 391
Car Washes ............................ 407
Carbon Monoxide Warning ................. 339
Cargo Light ............................ 95
Cargo (Vehicle Loading) ................... 342
Catalytic Converter ...................... 386
Caution, Exhaust Gas ...................... 75
CD (Compact Disc) Player ................. 250
CD (Compact Disc) Player Maintenance ........ 258
Cellular Phone .................. 85,250,251,258
Center High Mounted Stop Light ............ 423
Certification Label ....................... 342
Chains, Tire ............................ 329
Changing A Flat Tire ..................... 366
INDEX 447
10