2001 NISSAN SENTRA ignition

When performing any inspection or mainte-
nance work on your vehicle, always take
care to prevent serious accidental injury to
yourself or damage to the vehicle. The
following are general precautions which
should be closely observed.
WARNING
cPark the vehicle on a level surface,
apply the parking brake securely and
block the wheels to prevent the ve-
hicle from moving. For manual trans-
mission models, move the shift lever
to N (Neutral). For automatic trans-
mission models, move the shift se-
lector lever to P (Park).
cBe sure the ignition key is in the OFF
or LOCK position when performing
any parts replacement or repairs.
cYour vehicle is equipped with an
automatic engine cooling fan. It may
come on at any time without warn-
ing, even if the ignition key is in the
OFF position and the engine is not
running. To avoid injury, always dis-
connect the negative battery cable
before working near the fan.cIf you must work with the engine
running, keep your hands, clothing,
hair and tools away from moving
fans, belts and any other moving
parts.
cIt is advisable to secure or remove
any loose clothing and remove any
jewelry, such as rings, watches, etc.,
before working on your vehicle.
cAlways wear eye protection when-
ever you work on your vehicle.
cIf you must run the engine in an
enclosed space such as a garage, be
sure there is proper ventilation for
exhaust gases to escape.
cNever get under the vehicle while it
is supported only by a jack. If it is
necessary to work under the vehicle,
support it with safety stands.
cKeep smoking materials, flame and
sparks away from the fuel tank and
battery.cOn gasoline engine models with the
multiport fuel injection (MFI) system,
the fuel filter or fuel lines should be
serviced by an authorized NISSAN
dealer because the fuel lines are
under high pressure even when the
engine is off.
CAUTION
cDo not work under the hood while
the engine is hot. Turn the engine off
and wait until it cools down.
cNever connect or disconnect the bat-
tery or any transistorized compo-
nent while the ignition switch is in
the ON position.
cNever leave the engine or automatic
transmission related component
harnesses disconnected while the
ignition switch is in the ON position.
c
Avoid contact with used engine oil
and coolant. Improperly disposed
engine oil, engine coolant, and/or
other vehicle fluids can damage the
environment. Always conform to lo-
cal regulations for disposal of ve-
hicle fluid.
MAINTENANCE
PRECAUTIONS
8-2Do-it-yourself
ZX

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
unusual wear, cuts, fraying or looseness.
If the belt is in poor condition or loose,
have it replaced or adjusted by an autho-
rized NISSAN dealer.
2. Have the belts checked regularly for con-
dition and tension in accordance with the
maintenance schedule found in the``Maintenance'' section of this manual.
WDI0037
DRIVE BELTS
Do-it-yourself8-19
ZX

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
remove the spark plugs. An incorrect
socket can damage the spark plugs.
REPLACING SPARK PLUGS
Platinum-tipped spark plugs
It is not necessary to replace platinum-
tipped spark plugs as frequently as conven-
tional type spark plugs because they last
much longer. Follow 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. On the 1.8L engine, disconnect the igni-
tion coil connectors. Remove the ignition
coil bolts.
2. Disconnect the spark plug cables from
the spark plugs.
When disconnecting, always hold the
boots, not the cables. Mark all cables to
identify their original locations.
3. 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.
4. 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 to 22 ft-lb (20 to 29 Nzm)
DI1229MADI1100
SPARK PLUG
8-20Do-it-yourself
ZX

5. Holding the boot, reconnect each high
tension cable to its proper spark plug by
pushing it on until you feel a snap.
6. On the 1.8L engine, install the ignition
coil bolt.
Ignition coil bolt tightening torque:
33 to 44 in-lb (3.8 - 5.0 Nzm)
Connect the ignition coil connector.
The air cleaner filter should not be cleaned
and reused. Replace it according to the
maintenance intervals shown in the ``Main-
tenance'' section of this manual. When re-
placing the filter, wipe the inside of the air
cleaner housing and the cover with a damp
cloth.
WARNING
cOperating the engine with the air
cleaner removed can cause you or
others to be burned. The air cleaner
not only cleans the air, it stops theflame 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
Do-it-yourself8-21
ZX

CHECKING CLUTCH PEDAL
Press the pedal by hand and be sure the
free travel is within the limits shown above.
If free travel is out of the range shown
above, see an authorized NISSAN dealer.
CAUTION
Never use a fuse of higher amperage
rating than specified on the fuse box
cover. This could damage the electrical
system or cause a fire.
ENGINE COMPARTMENT
If any electrical equipment does not come
on, check for an open fuse.
1. Be sure the ignition switch and the head-
light switch are OFF.
2. Open the engine hood.3. Remove the fuse box cover.
4. Remove the fuse with the fuse puller.
The fuse puller is located in the center of
the fuse block in the passenger compart-
ment.
5. If the fuse is open, replace it with a new
fuse.
6. If a new fuse also opens, have the elec-
trical system checked and repaired by an
authorized NISSAN dealer.
Fusible links
If there is electrical equipment that does not
operate and fuses are in good condition,
check the fusible links. If any of these
fusible links are melted, replace with only
genuine NISSAN parts.WDI0045LDI0034
CLUTCH PEDAL FUSES
Do-it-yourself8-25
ZX

CAUTION
Never use a fuse of higher amperage
rating than specified. This could dam-
age the electrical system or cause a
fire.
PASSENGER COMPARTMENT
If any electrical equipment does not oper-
ate, check for an open fuse.
1. Be sure the ignition switch and the head-
light switch are OFF.
2. Remove the coin box.3. Remove the fuse with the fuse puller.
The fuse puller is located in the center of
the fuse block.
4. If the fuse is open, replace it with a new
fuse.
5. If a new fuse also opens, have the elec-
trical system checked and repaired by an
authorized NISSAN dealer.
ADI1142
Do-it-yourself8-27
ZX

of at least 87 AKI (Anti-Knock Index). How-
ever, you may use unleaded gasoline with
an octane rating as low as 85 AKI (Anti-
Knock Index) in high altitude areas (over
4,000 ft [1,219 m]) such as: Colorado, Mon-
tana, New Mexico, Utah, Wyoming, north-
eastern Nevada, southern Idaho, western
South Dakota, western Nebraska, and the
part of Texas which is directly south of New
Mexico.
Using unleaded gasoline with an octane
rating lower than stated above can cause
persistent, heavy ``spark knock.'' (``Spark
knock'' is a metallic rapping noise.) If
severe, this can lead to engine damage. If
you detect a persistent heavy spark
knock even when using gasoline of the
stated octane rating, or if you hear steady
spark knock while holding a steady
speed on level roads, have an authorized
NISSAN dealer correct the condition.
Failure to correct the condition is misuse
of the vehicle, for which NISSAN is not
responsible.
Incorrect ignition timing may result in spark
knock, after-run and/or overheating, which
may cause excessive fuel consumption or
engine damage. If any of the above symp-toms are encountered, have your vehicle
checked at an authorized NISSAN dealer or
other competent service facility.
However, now and then you may notice
light spark knock for a short time while
accelerating or driving up hills. This is
not a cause for concern, because you
get the greatest fuel benefit when there
is light spark knock for a short time
under heavy engine load.
10-4Technical and consumer information
ZX

ENGINE
ModelQG18DE SR20DE
Type Gasoline, 4-cycle, DOHC Gasoline, 4-cycle, DOHC
Cylinder arrangement 4-cylinder in-line 4-cylinder in-line
Bore ý Stroke in (mm) 3.150 ý 3.465 (80.0 ý 88.0) 3.386 ý 3.386 (86.0 ý 86.0)
Displacement cu in (cm
3) 107.94 (1,769) 121.92 (1,998)
Firing order1-3-4-2 1-3-4-2
Idle speed rpm
See the ``Emission Control label'' on the underside of the hood. Ignition timing degree (B.T.D.C.) at idle speed
degree/rpm
CO percentage at idle speed
[No air] %
Platinum-tipped type Platinum-tipped type Conventional type
Spark plug Hot PLFR4A-11 *1 Ð Ð
Standard PLFR5A-11 *1 PFR5G-11 *1 BKR5E *1
Cold PLFR6A-11 *1 PFR6G-11 *1, PFR7G-11 *1 BKR6E *1, BKR7E *1
Camshaft operation Timing chain Timing chain
Spark plug gap (Nominal) in (mm) 0.043 (1.1) 0.043 (1.1) 0.031 to 0.035 (0.8 to 0.9)
Generator belt size
Width ý Length in (mm)0.843 x 32.28, (21.4 x 820)
0.843 x 44.09, (21.4 x 1,120)*10.559 x 32.68, (14.2 x 830)
0.843 x 40.75, (21.4 x 1,035)*1
*1: Always check with the Parts Department at an authorized NISSAN dealer for the latest parts information.
*2: With air conditioner
The spark ignition system of this vehicle meets all requirements of the Canadian Interference-Causing Equipment Regulations.
SPECIFICATIONS
10-8Technical and consumer information
ZX