2004 NISSAN SENTRA ECU

1. Power steering fluid pump
2. Water pump
3. Generator
4. A/C compressor (if so equipped)
5. Crankshaft
6. Auto tensioner
REPLACING SPARK PLUGS
WARNING
Be sure the engine and ignition switch are
off and that the parking brake is engaged
securely.
CAUTION
Be sure to use the correct socket to re-
move the spark plugs. An incorrect socket
can damage the spark plugs.
Platinum-tipped spark plugs
It is not necessary to replace platinum-tipped
spark plugs as frequently as conventional type
spark plugs because they last much longer. Fol-
low the maintenance schedule, but do not reuse
the spark plugs by cleaning or regapping.
cAlways replace spark plugs with rec-
ommended or equivalent ones.
1. Remove the engine cover (QR25DE en-
gine) .
2. Disconnect the ignition coil connectors. Re-
move the ignition coil bolts.
QR25DE engine
WDI0225WDI0005
SPARK PLUGS
8-22Maintenance and do-it-yourself
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IN-CABIN MICROFILTER (if so
equipped)
The in-cabin microfilter restricts the entry of air-
borne dust and pollen particles and reduces
some objectionable outside odors. The filter is
located behind the glove box. Refer to the
“NISSAN Service and Maintenance Guide” for
change intervals.
To change the filter, perform the following proce-
dure:
1. Remove the glove box door by removing the
two lower hinge pins.2. Remove the two screws securing the glove
box frame.
3. Remove the two screws securing the glove
box door latch. Remove the latch by pulling it
down.
4. Remove the glove box frame by pulling it
away from the instrument panel to disen-
gage the retaining clips.
LDI0139LDI0140
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Replace the battery in the keyfob as follows:
s1Open the lid using a coin.
s2Remove the battery.
s3Install a new battery with the “+” facing
down.
Recommended battery: Sanyo CR2025 or
equivalent.
s4Close the lid securely.
Type A
WPD0116
BATTERY REPLACEMENT
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use of a winter traction device (tire chains or
cables) . The minimum clearances are determined
using the factory equipped tires. Other types may
damage your vehicle. Use chain tensioners when
recommended by the tire chain manufacturer to
ensure a tight fit. Loose end links of the tire chain
must be secured or removed to prevent the pos-
sibility of whipping action damage to the fenders
or underbody. If possible, avoid fully loading your
vehicle when using tire chains. In addition, drive
at a reduced speed. Otherwise, your vehicle may
be damaged and/or vehicle handling and perfor-
mance may be adversely affected.
Tire chains must be installed only on the
front wheels and not on the rear wheels.
Never install tire chains on a TEMPORARY USE
ONLY spare tire.
Do not use tire chains on dry roads. Driving with
chains in such conditions can cause damage to
the various mechanisms of the vehicle due to
some overstress.
CHANGING WHEELS AND TIRES
Tire rotation
NISSAN recommends rotating the tires every
7,500 miles (12,000 km) .
See “Flat tire” in the “In case of emergency”
section of this manual for tire replacing proce-
dures.
As soon as possible, tighten the wheel nuts
to the specified torque with a torque
wrench.
Wheel nut tightening torque:
80 ft-lb (108 N·m)The wheel nuts must be kept tightened to
specifications at all times. It is recom-
mended that wheel nuts be tightened to
specification at each tire rotation interval.
WARNING
cAfter rotating the tires, check and ad-
just the tire pressure.
cRetighten the wheel nuts when the ve-
hicle has been driven for 600 miles
(1,000 km) (also in cases of a flat tire,
etc.) .
cDo not include the spare tire in the tire
rotation.
cFor additional information regarding
tires, refer to “Important Tire Safety In-
formation” (US) or “Tire Safety Informa-
tion” (Canada) in the Warranty Informa-
tion Booklet.
WDI0258
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Steps for determining correct load
limit
1. Locate the statement “The combined weight
of occupants and cargo should never ex-
ceed XXX pounds” on your vehicle’s tire
placard.
2. Determine the combined weight of the driver
and passengers that will be riding in your
vehicle.
3. Subtract the combined weight of the driver
and passengers from XXX kilograms or XXX
pounds.4. The resulting figure equals the available
amount of cargo and luggage load capacity.
For example, if the XXX amount equals 1400
lbs. and there will be five 150 lb. passengers
in your vehicle, the amount of available cargo
and luggage load capacity is 650 lbs.
(1400-750 (5 * 150) = 650 lbs.)
5. Determine the combined weight of luggage
and cargo being loaded on the vehicle. That
weight may not safely exceed the available
cargo and luggage load capacity calculated
in Step 4.6. If your vehicle will be towing a trailer, load
from your trailer will be transferred to your
vehicle. Consult this manual to determine
how this reduces the available cargo and
luggage load capacity of your vehicle.
Before driving a loaded vehicle, confirm the you
do not exceed the Gross Vehicle Weight Rating
(GVWR) or the Gross Axle Weight Rating
(GAWR) for your vehicle. See “Measurement of
Weights” later in this section.
Also check tires for proper inflation pressures.
See the Tire and Loading label.
LOADING TIPS
cThe GVW must not exceed GVWR or
GAWR as specified on the F.M.V.S.S. certi-
fication label.
cDo not load the front and rear axle to the
GAWR. Doing so will exceed the GVWR.
WARNING
cProperly secure all cargo with ropes or
straps to help prevent it from sliding or
shifting. Do not place cargo higher than
the seatbacks. In a sudden stop or col-
lision, unsecured cargo could cause
personal injury.
WTI0091
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Tongue load
Keep the tongue load between9-11percent of
the total trailer load within the maximum tongue
load limits shown in the following Towing
Load/Specification Chart. If the tongue load be-
comes excessive, rearrange cargo to allow for
proper tongue load.
Maximum gross vehicle
weight/maximum gross axle weight
The gross vehicle weight of the towing vehicle
must not exceed the gross vehicle weight rating
(GVWR) shown on the F. M. V. S. S. certification
label. The gross vehicle weight equals the com-
bined weight of the unloaded vehicle, passen-
gers, luggage, hitch, trailer tongue load and any
other optional equipment. In addition, front or rear
gross axle weight must not exceed the gross axle
weight rating (GAWR) shown on the F. M. V. S. S.
certification label.
TOWING LOAD/SPECIFICATION
CHART
TOWING LOAD / SPECIFICATION CHART
UNIT: lb (kg)
MAXIMUM TOWING
LOAD1,000 (454)
MAXIMUM TONGUE
LOAD110 (49)
TOWING SAFETY
Trailer hitch
Choose a proper hitch for your vehicle and trailer.
A genuine NISSAN trailer hitch is available from
your NISSAN dealer (Canada only) . Make sure
the trailer hitch is securely attached to the ve-
hicle, to help avoid personal injury or property
damage due to sway caused by crosswinds,
rough road surfaces or passing trucks.
CAUTION
cDo not use axle-mounted hitches.
cThe hitch should not be attached to or
affect the operation of the impact-
absorbing bumper.
CA0009TI1012M
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cDo not modify the vehicle exhaust sys-
tem, brake system, etc. to install a
trailer hitch.
cTo reduce the possibility of additional
damage if your vehicle is struck from
the rear, where practical, remove the
hitch and/or receiver when not in use.
cAfter the hitch is removed, seal the bolt
holes to prevent exhaust fumes, water
or dust from entering the passenger
compartment.
cRegularly check that all trailer hitch
mounting bolts are securely mounted.
Tire pressures
cWhen towing a trailer, inflate the vehicle tires
to the recommended cold tire pressure indi-
cated on the tire placard.
cTrailer tire condition, size, load rating and
proper inflation pressure should be in accor-
dance with the trailer and tire manufacturer’s
specifications.
Safety chains
Always use suitable safety chains between your
vehicle and the trailer. The safety chains should
be crossed and should be attached to the hitch,not to the vehicle bumper or axle. Be sure to leave
enough slack in the chains to permit turning
corners.
Trailer lights
CAUTION
When splicing into the vehicle electrical
system, a commercially available power-
type module/converter must be used to
provide power for all trailer lighting. This
unit uses the vehicle battery as a direct
power source for all trailer lights while
using the vehicle tail light, stoplight and
turn signal circuits as a signal source. The
module/converter must draw no more
that 15 milliamps from the stop and tail
lamp circuits. Using a module/converter
that exceeds these power requirements
may damage the vehicle’s electrical sys-
tem. See a reputable trailer dealer to ob-
tain the proper equipment and to have it
installed.
Trailer lights should comply with federal and/or
local regulations. For assistance in hooking up
trailer lights, contact a NISSAN dealer or repu-
table trailer dealer.
Trailer brakes
If your trailer is equipped with a braking system,
make sure it conforms to federal and/or local
regulations and that it is properly installed.
WARNING
Never connect a trailer brake system di-
rectly to the vehicle brake system.
Pre-towing tips
cBe certain your vehicle maintains a level
position when a loaded and/or unloaded
trailer is hitched. Do not drive the vehicle if it
has an abnormal nose-up or nose-down
condition; check for improper tongue load,
overload, worn suspension or other possible
causes of either condition.
cAlways secure items in the trailer to prevent
load shift while driving.
cBe certain your rearview mirrors conform to
all federal, state or local regulations. If not,
install any mirrors required for towing before
driving the vehicle.
Technical and consumer information9-17
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Trailer towing tips
In order to gain skill and an understanding of the
vehicle’s behavior, you should practice turning,
stopping and backing up in an area which is free
from traffic. Steering stability and braking perfor-
mance will be somewhat different than under
normal driving conditions.
cAlways secure items in the trailer to prevent
load shift while driving.
cAvoid abrupt starts, acceleration or stops.
cAvoid sharp turns or lane changes.
cAlways drive your vehicle at a moderate
speed.
cAlways block the wheels on both vehicle and
trailer when parking. Parking on a slope is
not recommended; however, if you must do
so, and if your vehicle is equipped with an
automatic transmission, first block the
wheels and apply the parking brake, and
then move the transmission shift selector
lever into the P (Park) position. If you move
the shift selector lever to the P (Park) posi-
tion before blocking the wheels and applying
the parking brake, transmission damage
could occur.
cWhen going down a hill, shift into a lower
gear and use the engine braking effect.When going up a long grade, downshift the
transmission to a lower gear and reduce
speed to reduce chances of engine over-
loading and/or overheating. However, for
long steep grades, do not stay in 1st or 2nd
gear when driving above 35 MPH (56 km/h) .
cIf the engine coolant rises to an extremely
high temperature when the air conditioner
system is on, turn off the air conditioner.
Coolant heat can be additionally vented by
opening the windows, switching the fan
control to high and setting the temperature
control to the HOT position.
cTrailer towing requires more fuel than normal
circumstances.
cAvoid towing a trailer for your vehicle’s first
500 miles (805 km) .
cFor the first 500 miles that you do tow, do
not drive over 50 MPH (80 km/h) .
cHave your vehicle serviced more often than
at intervals specified in the recommended
Maintenance Schedule in the “NISSAN Ser-
vice and Maintenance Guide”.
cWhen making a turn, your trailer wheels will
be closer to the inside of the turn than your
vehicle wheels. To compensate for this,
make a larger than normal turning radius
during the turn.cCrosswinds and rough roads will adversely
affect vehicle/trailer handling, possibly caus-
ing vehicle sway. When being passed by
larger vehicles, be prepared for possible
changes in crosswinds that could affect ve-
hicle handling. If swaying does occur, firmly
grip the steering wheel, steer straight ahead,
and immediately (but gradually) reduce ve-
hicle speed. This combination will help sta-
bilize the vehicle. Never increase speed.
cBe careful when passing other vehicles.
Passing while towing a trailer requires con-
siderably more distance than normal pass-
ing. Remember, the length of the trailer must
also pass the other vehicle before you can
safely change lanes.
cTo maintain engine braking efficiency and
electrical charging performance, do not use
5th gear (manual transmission) or overdrive
(automatic transmission) .
cAvoid holding the brake pedal down too long
or too frequently. This could cause the
brakes to overheat, resulting in reduced
braking efficiency.
When towing a trailer, transmission
oil/fluid should be changed more fre-
quently. For additional information, see the
“Maintenance and do-it-yourself” section
earlier in this manual.
9-18Technical and consumer information
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