
JUMP STARTING
If jump starting is necessary, see “Jump starting”
in the “In case of emergency” section of this
manual. If the engine does not start by jump
starting, the battery may have to be replaced.
Contact a NISSAN dealer.
1. Power steering oil pump
2. Water pump
3. Idler
4. Generator
5. A/C compressor
6. Crankshaft
: Tension checking points
WARNING
Be sure the ignition key is in the OFF or
LOCK position. The engine could rotate
unexpectedly.1. Visually inspect each belt for signs of un-
usual wear, cuts, fraying or looseness. If the
belt is in poor condition or is loose, have it
replaced or adjusted by a NISSAN dealer.
2. Have the belts checked regularly for condi-
tion and tension in accordance with the
maintenance schedule found in the
“NISSAN Service and Maintenance Guide”.
LDI0302
QG18DE engine
WDI0191
DRIVE BELTS
Maintenance and do-it-yourself8-21
ZREVIEW COPY:Ð2004 Sentra(b15)
Owners Manual(owners)ÐUSA English(nna)
03/18/04Ðtbrooks
X

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
ZREVIEW COPY:Ð2004 Sentra(b15)
Owners Manual(owners)ÐUSA English(nna)
03/18/04Ðtbrooks
X

3. Disconnect the ignition coils from the spark
plugs.
4. Remove the spark plugs with a spark plug
socket.
The plug socket has a rubber seal that holds
the spark plug so it does not fall when it is
pulled out. Make sure each spark plug is
snugly fitted into the spark plug socket.
5. Fit the new plugs, one at a time, into the
spark plug socket and install them.Use
only the specified spark plugs.Turn
each plug several full turns by hand, then
tighten with the spark plug socket to the
correct torque. Do not overtighten.
Spark plug tightening torque:
14 - 22 ft-lb (20 - 29 N·m)
6. Holding the boot, reconnect each high ten-
sion cable/ignition coil to its proper spark
plug by pushing it on until you feel a snap.
7. Install the ignition coil bolts.
Ignition coil bolt tightening torque:
33 - 44 in-lb (3.8 - 5.0 N·m)
Connect the ignition coil connector.
8. Install the engine cover (GR25DE engine) .The air cleaner filter should not be cleaned and
reused. Replace it according to the maintenance
intervals shown in the “NISSAN Service and
Maintenance Guide.” When replacing the filter,
wipe the inside of the air cleaner filter housing
and the cover with a damp cloth.WARNING
cOperating the engine with the air
cleaner removed can cause you or oth-
ers to be burned. The air cleaner not
only cleans the air, it stops the flame if
the engine backfires. If it isn’t there, and
the engine backfires, you could be
burned. Do not drive with the air cleaner
removed, and be careful when working
on the engine with the air cleaner
removed.
cNever pour fuel into the throttle body or
attempt to start the engine with the air
cleaner removed. Doing so could result
in serious injury.
ADI0631
AIR CLEANER
Maintenance and do-it-yourself8-23
ZREVIEW COPY:Ð2004 Sentra(b15)
Owners Manual(owners)ÐUSA English(nna)
03/18/04Ðtbrooks
X

Self-adjusting brakes
Your vehicle is equipped with self-adjusting
brakes.
The front (and rear, if so equipped) disc-type
brakes self-adjust every time the brake pedal is
applied. The rear drum-type brakes also self-
adjust every time the brake pedal is applied.
If the brake pedal goes down farther than normal,
it may be due to a lack of adjustment of the rear
drum brakes. To adjust, apply the parking brake
several times.
WARNING
See a NISSAN dealer for a brake system
check if the brake pedal height does not
return to normal.
Brake pad wear indicators
The disc brake pads on your vehicle have audible
wear indicators. When a brake pad requires re-
placement, a high pitched scraping or screech-
ing sound will be heard when the vehicle is in
motion. The noise will be heard whether or not the
brake pedal is depressed. Have the brakes
checked as soon as possible if the wear indicator
sound is heard.
Under some driving or climate conditions, occa-
sional brake squeak, squeal or other noise maybe heard. Occasional brake noise during light to
moderate stops is normal and does not affect the
function or performance of the brake system.
The rear drum brakes (if so equipped) do not
have audible wear indicators. Should you ever
hear an unusually loud noise from the rear drum
brakes, have them inspected as soon as possible
by a NISSAN dealer.
Proper brake inspection intervals should
be followed.For more information regarding
brake inspections, see the appropriate mainte-
nance schedule information in the “NISSAN Ser-
vice and Maintenance Guide”.
BRAKE BOOSTER
Check the brake booster function as follows:
1. With the engine off, press and release the
brake pedal several times. When brake
pedal movement (distance of travel) remains
the same from one pedal application to the
next, continue on to the next step.
2. While depressing the brake pedal, start the
engine. The pedal height should drop a little.
3. With the brake pedal depressed, stop the
engine. Keep the pedal depressed for about
30 seconds. The pedal height should not
change.4. Run the engine for one minute without de-
pressing the brake pedal, then turn it off.
Depress the brake pedal several times. The
pedal travel distance will decrease gradually
with each depression as the vacuum is re-
leased from the booster.
If the brakes do not operate properly, have the
brakes checked by a NISSAN dealer.
Maintenance and do-it-yourself8-29
ZREVIEW COPY:Ð2004 Sentra(b15)
Owners Manual(owners)ÐUSA English(nna)
03/18/04Ðtbrooks
X

If you have a flat tire, see the “In case of
emergency” section of this manual.
TIRE PRESSURE
Tire inflation pressure
Check the tire pressures (including the spare)
often and always prior to long distance trips. The
recommended tire pressure specifications are
shown on the Tire and Loading Information label
(this label is also known as the tire placard) under
the9Recommended Cold Tire Inflation Pressure9
heading. The Tire and Loading Information label
is affixed to the driver side center pillar. Tire
pressures should be checked regularly because:
cMost tires naturally lose air over time.
cTires can lose air suddenly when driven over
potholes or other objects or if the vehicle
strikes a curb while parking.
The tire pressures should be checked when the
tires are cold. The tires are considered COLD
after the vehicle has been parked for 3 or more
hours, or driven less than 1 mile (1.6 km) at
moderate speeds.
Incorrect tire pressure, including under in-
flation, may adversely affect tire life and
vehicle handling.
WARNING
cImproperly inflated tires can fail sud-
denly and cause an accident.
cThe vehicle weight capacity is indicated
on the Tire and Loading Information
label. Do not load your vehicle beyond
this capacity. Overloading your vehicle
may result in reduced tire life, unsafe
operating conditions due to premature
tire failure, or unfavorable handling
characteristics and could also lead to a
serious accident. Loading beyond the
specified capacity may also result in
failure of other vehicle components.
cBefore taking a long trip, or whenever
you heavily load your vehicle, use a tire
pressure gauge to ensure that the tire
pressures are at the specified level.
cDo not drive your vehicle over 85 MPH
(137 km/h) unless it is equipped with
high speed rated tires. Driving faster
than 85 MPH (137 km/h) may result in
tire failure, loss of control and possible
injury.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.
WHEELS AND TIRES
Maintenance and do-it-yourself8-39
ZREVIEW COPY:Ð2004 Sentra(b15)
Owners Manual(owners)ÐUSA English(nna)
03/18/04Ðtbrooks
X

ticular side that must always face outward when
mounted on a vehicle.
TYPES OF TIRES
WARNING
cWhen changing or replacing tires, be
sure all four tires are of the same type
(i.e., Summer, All Season or Snow) and
construction. A NISSAN dealer may be
able to help you with information about
tire type, size, speed rating and
availability.
cReplacement tires may have a lower
speed rating than the factory equipped
tires, and may not match the potential
maximum vehicle speed. Never exceed
the maximum speed rating of the tire.
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.
All season tires
NISSAN specifies All Season tires on some mod-
els to provide good performance all year, includ-
ing snowy and icy road conditions. All Season
tires are identified by ALL SEASON and/or M&Son the tire sidewall. Snow tires have better snow
traction than All Season tires and may be more
appropriate in some areas.
Summer tires
NISSAN specifies summer tires on some models
to provide superior performance on dry roads.
Summer tire performance is substantially re-
duced in snow and ice. Summer tires do not have
the tire traction rating “M&S” on the tire sidewall.
If you plan to operate your vehicle in snowy or icy
conditions, NISSAN recommends the use of
SNOW tires or ALL SEASON tires on all four
wheels.
Snow tires
If snow tires are needed, it is necessary to select
tires equivalent in size and load rating to the
original equipment tires. If you do not, it can
adversely affect the safety and handling of your
vehicle.
Generally, snow tires have lower speed ratings
than factory equipped tires and may not match
the potential maximum vehicle speed. Never ex-
ceed the maximum speed rating of the tire.
If you install snow tires, they must be the same
size, brand, construction and tread pattern on all
four wheels.For additional traction on icy roads, studded tires
may be used. However, some U.S. states and
Canadian provinces prohibit their use. Check
local, state and provincial laws before installing
studded tires. Skid and traction capabilities of
studded snow tires on wet or dry surfaces may be
poorer than that of non-studded snow tires.
TIRE CHAINS
WARNING
Tire chains/cables cannot be installed on
P215/45ZR17 size tires. Installation of the
tire chains/cables on P215/45ZR17 size
tires will cause damage to the vehicles. If
you plan to use tire chains/cables, you
should install P195/55R16 size tires on
your vehicle.
Use of tire chains may be prohibited according to
location. Check the local laws before installing
tire chains. When installing tire chains, make sure
they are the proper size for the tires on your
vehicle and are installed according to the chain
manufacturer’s suggestions.Use only SAE
class “S” chains.Class9S9chains are used on
vehicles with restricted tire to vehicle clearance.
Vehicles that can use Class “S” chains are de-
signed to meet the minimum clearances between
the tire and the closest vehicle suspension or
body component required to accommodate the
Maintenance and do-it-yourself8-45
ZREVIEW COPY:Ð2004 Sentra(b15)
Owners Manual(owners)ÐUSA English(nna)
03/18/04Ðtbrooks
X

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
8-46Maintenance and do-it-yourself
ZREVIEW COPY:Ð2004 Sentra(b15)
Owners Manual(owners)ÐUSA English(nna)
03/18/04Ðtbrooks
X

1. Wear indicator
2. Location mark
Tire wear and damage
WARNING
cTires should be periodically inspected
for wear, cracking, bulging or objects
caught in the tread. If excessive wear,
cracks, bulging or deep cuts are found,
the tire(s) should be replaced.cThe original tires have built-in tread
wear indicators. When the wear indica-
tors are visible, the tire(s) should be
replaced.
cImproper service of the spare tire may
result in serious personal injury. If it is
necessary to repair the spare tire, con-
tact a NISSAN dealer.
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.
Replacing wheels and tires
When replacing a tire, use the same size, tread
design, speed rating and load carrying capacity
as originally equipped. Recommended types and
sizes are shown in “Wheels and tires” in the
“Technical and consumer information” section of
this manual.
WARNING
cThe use of tires other than those recom-
mended or the mixed use of tires of
different brands, construction (bias,
bias-belted or radial) , or tread patterns
can adversely affect the ride, braking,
handling, ground clearance, body-to-
tire clearance, tire chain clearance,
speedometer calibration, headlight aim
and bumper height. Some of these ef-
fects may lead to accidents and could
result in serious personal injury.
cIf the wheels are changed for any rea-
son, always replace with wheels which
have the same off-set dimension.
Wheels of a different off-set could
cause premature tire wear, degrade ve-
hicle handling characteristics and/or
interference with the brake
discs/drums. Such interference can
lead to decreased braking efficiency
and/or early brake pad/shoe wear. Re-
fer to “Wheels and tires” in the “Techni-
cal and consumer information” section
of this manual for wheel off-set
dimensions.
WDI0259
Maintenance and do-it-yourself8-47
ZREVIEW COPY:Ð2004 Sentra(b15)
Owners Manual(owners)ÐUSA English(nna)
03/18/04Ðtbrooks
X