engine DODGE CARAVAN 2004 4.G Workshop Manual

2.4L ENGINE
298 MAINTAINING YOUR VEHICLE

3.3L/3.8L ENGINES
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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 dealer for service as soon as
possible.CAUTION!
Prolonged driving with the ªMalfunction Indicator
Lightº on could cause further damage to the emis-
sion control system. It could also affect fuel economy
and driveability. The vehicle must be serviced before
any emissions tests can be performed.
If the ªMalfunction Indicator Lightº is flashing
while the engine is running, severe catalytic con-
verter damage and power loss will soon occur. Im-
mediate service is required.
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EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle's emissions control system.
Failure to pass could prevent vehicle registration.
For states which have an I/M (Inspection and
Maintenance) requirement, this check verifies the
following: the MIL (Malfunction Indicator Lamp)
is functioning and is not on when the engine is running,
and that the OBD (On Board Diagnostic) system is ready
for testing.
Normally, the OBD system will be ready. The OBD
system maynotbe ready if your vehicle was recently
serviced, if you recently had a dead battery, or a battery
replacement. If the OBD system should be determined
not ready for the I/M test, your vehicle may fail the test.Your vehicle has a simple ignition key actuated test
which you can use prior to going to the test station. To
check if your vehicle's OBD system is ready, you must do
the following:
1. Insert your 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 your key to the ON position, you
will see your 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 off the
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ignition key or start the engine. This means that your
vehicle's OBD system isnot readyand you shouldnot
proceed 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 your vehicle's OBD system
isreadyand you can proceed to the I/M station.
If your OBD system isnot ready,you should see your
authorized dealer or repair facility. If your vehicle was
recently serviced or had a battery failure or replacement,
you may need to do nothing more than drive your
vehicle as you normally would in order for your OBD
system to update. A recheck with the above test routine
may then indicate that the system is now ready.
Regardless of whether your vehicle's OBD system is
ready or not ready, if the MIL symbol is illuminated
during normal vehicle operation, you should have yourvehicle serviced before going to the I/M station. The I/M
station can fail your vehicle because the MIL symbol is on
with the engine running.
REPLACEMENT PARTS
Use of genuine Mopartparts for normal/scheduled
maintenance and repairs is highly recommended to in-
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.
DEALER SERVICE
Your dealer has the qualified service personnel, 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 manuals before attempting any procedure
yourself.
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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. Do only that 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.
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.
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The best time to check the engine oil level is about 5
minutes after a fully warmed engine is shut off or before
starting the engine after it has sat overnight.
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.
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Change Engine Oil
Road conditions and your kind of driving affects the
interval at which your oil should be changed. Check the
following list to see if any apply to you.
²Day or night temperatures are below 32ÉF (0ÉC).
²Stop and Go driving.
²Extensive engine idling.
²Driving in dusty conditions.
²Short trips of less than 10 miles (16 km).
²More than 50% of your driving is at sustained high
speeds during hot weather, above 90ÉF (32ÉC).
²Trailer towing.
²Taxi, Police or delivery service (commercial service).
²Off-Road or desert operation.IfANYof these apply to you, then change your engine oil
at every interval shown in schedule ªBº of the ªMainte-
nance Schedulesº section of this manual.
If none of these apply to you, then change your engine oil
at every interval shown on schedule ªAº of the ªMain-
tenance Schedulesº section of this manual
NOTE:Under no circumstances should oil change in-
tervals exceed 6000 miles (10 000 km) or 6 months
whichever comes first.
Engine Oil Selection
For best performance and maximum protection under all
types of operating conditions, the manufacture only
recommends engine oils that are API certified and meet
the requirements of DaimlerChrysler Material Standard
MS-6395. Use Mopar or an equivalent oil meeting the
specification MS-6395.
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American Petroleum Institute (API) Engine Oil
Identification Symbol
This symbol means that the oil has
been certified by the American
Petroleum Institute (API). The
manufacture only recommends
API Certified engine oils that
meet the requirements of
DaimlerChrysler Material Stan-
dard MS-6395. Use Mopar or an
equivalent oil meeting the specifi-
cation MS-6395.
Engine Oil Viscosity Chart
The proper SAE viscosity grade of engine oil should be
selected based on the following recommendation and be
within the operating temperature shown in the engine oil
viscosity chart.
²SAE 5W-30engine oil is preferred. SAE 5W-30 engine
oils improve low temperature starting and helps ve-
hicle fuel economy.
Lubricants which do not have both, the engine oil certi-
fication mark and the correct SAE viscosity grade num-
ber should not be used.
306 MAINTAINING YOUR VEHICLE

Synthetic Engine Oils
There are a number of engine oils being promoted as
either synthetic or semi-synthetic. If you chose to use
such a product, useonlythose oils that meet the Ameri-
can Petroleum Institute (API) and SAE viscosity stan-
dard. Follow the service schedule that describes your
driving type.
Materials Added to Engine Oil
The manufacture strongly recommends against the addi-
tion of any additives (other than leak detection dyes) to
the engine oil. Engine oil is an engineered product and
it's performance may be impaired by supplemental ad-
ditives.
Disposing of Used Engine Oil And Oil Filters
Care should be taken in disposing of used engine oil and
oil filters from your vehicle. Used oil and oil filters,
indiscriminately discarded, can present a problem to the
environment. Contact your dealer, service station, orgovernmental agency for advice on how and where used
oil and oil filters can be safely discarded in your area.
Engine Oil Filter
The engine oil filter should be replaced at every engine
oil change.
Engine Oil Filter Selection
All the manufacturers engines have a full-flow type oil
filter. Use a filter of this type for replacement. The quality
of replacement filters varies considerably. Only high
quality filters should be used to assure most efficient
service. Mopar Engine Oil Filters are a high quality oil
filter and are recommended.
Drive Belts Ð Check Condition and Tension
At the mileage indicated in the maintenance schedule, all
belts should be checked for condition and proper tension.
Improper belt tension can cause belt slippage and failure.
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