2008 DODGE GRAND CARAVAN engine

4.0L ENGINE COMPARTMENT
436 MAINTAINING YOUR VEHICLE

ONBOARD DIAGNOSTIC SYSTEM Ð 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 ªMalfunction Indicator Light.º 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 authorized dealer for service as
soon as possible.CAUTION!
²Prolonged driving with the ªMalfunction Indica-
tor Lightº 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.
²If the ªMalfunction Indicator Lightº is flashing
while the engine is running, severe catalytic con-
verter damage and power loss will soon occur.
Immediate service is required.
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Loose Fuel Filler Cap Message Ð gASCAP
Should the ªLoose Fuel Filler Capº or ªgASCAPº mes-
sage appear, there may be a problem in the evaporative
system. Before taking the vehicle into an authorized
dealer, check first to see if the fuel filler cap is possibly
loose, improperly installed, or damaged. A loose fuel
filler cap message will be displayed in the instrument
cluster. Tighten the gas cap until a9clicking9sound is
heard. This is an indication that the gas cap is properly
tightened. Press the odometer reset button to turn the
message off. If the problem persists, the message will
appear the next time the vehicle is started. If the problem
is detected twice in a row, the system will turn on the
Malfunction Indicator Light (MIL). Resolving the prob-
lem will turn the MIL light off. Take your vehicle in to an
authorized dealer.
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of this vehicle's emissions control system.
Failure to pass could prevent vehicle registration.
For states that require an Inspection and Mainte-
nance (I/M), this check verifies the Malfunction
Indicator Light (MIL) is functioning and is not on
when the engine is running, and that the OBD II system
is ready for testing.
Normally, the OBD II system will be ready. The OBD II
system maynotbe ready if the vehicle was recently
serviced, recently had a dead battery, or a battery replace-
ment. If the OBD II system should be determined not
ready for the I/M test, the vehicle may fail the test.
438 MAINTAINING YOUR VEHICLE

This vehicle has a simple ignition key-actuated test,
which you can use prior to going to the test station. To
check if this vehicle's OBD II system is ready, you must
do the following:
1. Insert the ignition key into the ignition switch.
2. Turn the ignition to the ON position, but do not crank
or start the engine.
3. If you crank or start the engine, you will have to start
this test over.
4. As soon as you turn the ignition key to the ON
position, you will see the MIL symbol come on as part of
a normal bulb check.
5. Approximately 15 seconds later, one of two things will
happen:
a. The MIL will flash for about 10 seconds and then
return to being fully illuminated until you turn OFFthe ignition key or start the engine. This means that the
vehicle's OBD II system isnot readyand you should
notproceed to the I/M station.
b. The MIL will not flash at all and will remain fully
illuminated until you turn OFF the ignition key or start
the engine. This means that the vehicle's OBD II
system isready,and you can proceed to the I/M
station.
If the OBD II system isnot ready,you should see an
authorized dealer or repair facility. If this vehicle was
recently serviced or had a battery failure or replacement,
you may need to do nothing more than drive the vehicle
as you normally would in order for the OBD II system to
update. A recheck with the above test routine may then
indicate that the system is now ready.
Regardless of whether the vehicle's OBD II system is
ready or not ready, if the MIL is illuminated during
normal vehicle operation, you should have the vehicle
MAINTAINING YOUR VEHICLE 439
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serviced before going to the I/M station. The I/M station
can fail the vehicle because the MIL is on with the engine
running.
REPLACEMENT PARTS
Use of genuine Mopartparts for normal/scheduled
maintenance and repairs is highly recommended to en-
sure the designed performance. Damage or failures
caused by the use of non-Mopartparts for maintenance
and repairs will not be covered by the manufacturer's
warranty.
AUTHORIZED DEALER SERVICE
Your authorized dealer has the qualified service person-
nel, special tools, and equipment to perform all service
operations in an expert manner. Service manuals are
available which include detailed service information for
your vehicle. Refer to these service manuals before
attempting any procedure yourself.NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
WARNING!
You can be badly injured working on or around a
motor vehicle. Only do service work for which you
have the knowledge and the proper equipment. If
you have any doubt about your ability to perform a
service job, take your vehicle to a competent
mechanic.
440 MAINTAINING YOUR VEHICLE

MAINTENANCE PROCEDURES
The pages that follow contain therequiredmaintenance
services determined by the engineers who designed your
vehicle.
Besides the maintenance items for which there are fixed
maintenance intervals, there are other items that should
operate satisfactorily without periodic maintenance.
However, if a malfunction of these items does occur, it
could adversely affect the engine or vehicle performance.
These items should be inspected if a malfunction is
observed or suspected.
ENGINE OIL
Checking Oil Level
To assure proper engine lubrication, the engine oil must
be maintained at the correct level. Check the oil level at
regular intervals, such as every fuel stop.
The best time to check the engine oil level is about five
minutes after a fully warmed engine is shut off or before
starting the engine after it has sat overnight.
MAINTAINING YOUR VEHICLE 441
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Checking the oil while the vehicle is on level ground will
improve the accuracy of the oil level readings. Maintain
the oil level between the MIN and MAX markings on the
dipstick. Adding one quart of oil when the reading is at
the MIN mark will result in a MAX reading on these
engines.CAUTION!
Overfilling or underfilling will cause oil aeration or
loss of oil pressure. This could damage your engine.
Change Engine Oil
The oil change indicator system will remind you that it is
time to take your vehicle in for scheduled maintenance.
Refer to ªMaintenance Scheduleº in Section 8 of this
manual for information on this system.
NOTE: Under no circumstances should oil change
intervals exceed 6,000 miles (10 000 km) or six months,
whichever occurs first.
Engine Oil Selection
For best performance and maximum protection under all
types of operating conditions, the manufacturer only
Engine Oil Dipstick
442 MAINTAINING YOUR VEHICLE

recommends engine oils that are API certified and meet
the requirements of DaimlerChrysler Material Standard
MS-6395.
American Petroleum Institute (API) Engine Oil
Identification Symbol
This symbol means that the oil has
been certified by the American
Petroleum Institute (API). The
manufacturer only recommends
API Certified engine oils.
Engine Oil Viscosity (SAE Grade) Ð 3.3L & 3.8L
Gasoline Engines
SAE 5W-20 engine oil is recommended for all operating
temperatures. This engine oil improves low temperaturestarting and vehicle fuel economy. Your engine oil filler
cap also shows the recommended engine oil viscosity for
your vehicle.
For information on engine oil filler cap location, refer to
the Engine Compartment illustration in this section.
Lubricants which do not have both, the engine oil certi-
fication mark and the correct SAE viscosity grade num-
ber should not be used.
Engine Oil Viscosity (SAE Grade) Ð 4.0 Liter
Engines
SAE 10W-30engine oil is preferred for all operating
temperatures. The engine oil filler cap also shows the
recommended engine oil viscosity for your vehicle.
Lubricants which DO NOT have both, the engine oil
certification mark and the correct SAE viscosity grade
number should not be used.
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