'99camry U
178
Getting more kilometers/mileage from a
liter/gallon of fuel is easyÐjust take it
easy. It will help make your vehicle last
longer, too. Here are some specific tips
on how to save money on both fuel and
repairs:
Keep your tires inflated at the cor-
rect pressure. Underinflation causes
tire wear and wastes fuel. See Chapter
7±2 for instructions.
Do not carry unneeded weight in
your vehicle. Excess weight puts a
heavier load on the engine, causing
greater fuel consumption.
Avoid lengthy warm±up idling. Once
the engine is running smoothly, begin
drivingÐbut gently. Remember, howev-
er, that on cold winter days this may
take a little longer.
Accelerate slowly and smoothly.
Avoid jackrabbit starts. Get into high
gear as quickly as possible.
Avoid long engine idling. If you have
a long wait and you are not in traffic,
it is better to turn off the engine and
start again later.
Avoid engine lug or overrevving. Use
a gear position suitable for the road on
which you are travelling.
Avoid continuous speeding up and
slowing down. Stop±and±go driving
wastes fuel.
Avoid unnecessary stopping and
braking. Maintain a steady pace. Try
to time the traffic signals so you only
need to stop as little as possible or
take advantage of through streets to
avoid traffic lights. Keep a proper dis-
tance from other vehicles to avoid sud-
den braking. This will also reduce wear
on your brakes.
Avoid heavy traffic or traffic jams
whenever possible.
Do not rest your foot on the clutch
or brake pedal. This causes needless
wear, overheating and poor fuel econo-
my.
Maintain a moderate speed on high-
ways. The faster you drive,the greater
the fuel consumption. By reducing your
speed, you will cut down on fuel con-
sumption.
Keep the front wheels in proper
alignment. Avoid hitting the curb and
slow down on rough roads. Improper
alignment not only causes faster tire
wear but also puts an extra load on
the engine, which, in turn, wastes fuel.
Keep the bottom of your vehicle free
from mud, etc. This not only lessens
weight but also helps prevent corro-
sion.
Keep your vehicle tuned±up and in
top shape. A dirty air cleaner, improp-
er valve clearance, dirty plugs, dirty oil
and grease,brakes not adjusted, etc. all
lower engine performance and contrib-
ute to poor fuel economy. For longer
life of all parts and lower operating
costs, keep all maintenance work on
schedule, and if you often drive under
severe conditions, see that your vehicle
receives more frequent maintenance
(For scheduled maintenance informa-
tion, please refer to the separate
ºScheduled Maintenance Guideº or
ºOwner 's Manual Supplementº).
How to save fuel and make
your vehicle last longer, too
'99camry U
185
If your engine coolant temperature
gauge indicates overheating, if you ex-
perience a loss of power, or if you hear
a loud knocking or pinging noise, the
engine has probably overheated. You
should follow this procedure...
1. Pull safely off the road, stop the ve-
hicle and turn on your emergency
flashers. Put the transmission in ºPº
(automatic) or neutral (manual) and ap-
ply the parking brake. Turn off the air
conditioning if it is being used.
2. If coolant or steam is boiling out of the
radiator or reservoir,stop the engine.
Wait until the steam subsides before
opening the hood. If there is no coolant
boiling over or steam, leave the engine
running and make sure the electric
cooling fan is operating. If it is not,
turn the ignition off.
CAUTION
To help avoid personal injury, keep
the hood closed until there is no
steam. Escaping steam or coolant is
a sign of very high pressure.
3. Look for obvious coolant leaks from the
radiator, hoses,and under the vehicle.
However, note that water draining from
the air conditioning is normal if it has
been used.
CAUTION
When the engine is running, keep
hands and clothing away from the
moving fan and engine drive belts.
4. If the coolant is leaking, stop the en-
gine immediately. Call a Toyota dealer
for assistance.
5. If there are no obvious leaks, check
the coolant reservoir. If it is dry, add
coolant to the reservoir while the en-
gine is running. Fill it about half full.
CAUTION
Do not attempt to remove the radiator
cap when the engine and radiator are
hot. Serious injury could result from
scalding hot fluid and steam blown
out under pressure.
6. After the engine coolant temperature
has cooled to normal, again check the
coolant level in the reservoir. If neces-
sary, bring it up to half full again. Seri-
ous coolant loss indicates a leak in the
system. You should have it checked as
soon as possible at your Toyota dealer.
If your vehicle overheats
NEW FEATURES Ð 5S-FNE ENGINE
NEW FEATURES
6
5S-FNE ENGINE
DESCRIPTION
The 5S-FNE engine is a new engine that uses CNG (Compressed Natural Gas) as fuel, which has been
developed based on the 5S-FE gasoline engine.
The main component of natural gas is methane (CH
4), which has fewer carbons (C) than gasoline (mean
molecular formula: C
7.5H13.4). Therefore, the amount of CO2 discharged by this engine is approximately
70% that of the gasoline engine. Furthermore, this engine achieves low-emission operation by precisely
controlled air-fuel ratio and using special catalysts for the CNG application.
However, because the fuel is in the gaseous form, its volumetric efficiency is low, causing lower power
output if this fuel is used in the base engine.
Therefore, the 5S-FNE engine has adopted the following features: a high compression ratio, the intake
valves with early closed timing, the intake and exhaust valves with increased lift, a low back pressure muffler
made possible by the 2-way exhaust system, injectors for gaseous fuel, and a catalytic converter designed
exclusively for CNG application. At the same time, precision air-fuel ratio control is effected through the
use of the air-fuel ratio sensor* and the heater oxygen sensor, thus achieving the level of performance that
is equivalent to the base engine. Moreover, this engine realizes extremely low emissions and restoring engine
torque.
*: Already adopted on the California specification 5S-FE engine.
Specifications
Item
5S-FNE Engine5S-FE Engine
No. of Cyls. & Arrangement4-Cylinder, In-Line
Valve Mechanism16-Valve DOHC,
Belt & Gear Drive
Combustion CamberPentroof Type
ManifoldsCross-Flow
Fuel SystemSFI
Displacement cm3 (cu. in.)2164 (132.0)
Bore Stroke mm (in.)87.0 91.0 (3.43 3.58)
Compression Ratio11.0 : 19.5 : 1
Max. Output [SAE-NET]88 kW @ 5200 rpm
(118 HP @ 5200 rpm)
99 kW @ 5200 rpm
(133 HP @ 5200 rpm)
97 kW @ 5200 rpm*
(130 HP @ 5200 rpm)*
Max. Torque [SAE-NET]178 N´m @ 2400 rpm
(131 ft´lbf @ 2400 rpm)
199 N´m @ 4400 rpm
(147 ft´lbf @ 4400 rpm)
197 N´m @ 4400 rpm*
(145 ft´lbf @ 4400 rpm)*
IntakeOpen35 BTDC
Valve
IntakeClose385 ABDC435 ABDCValve
Timing
ExhaustOpen455 BBDCExhaustClose35 AT D C
Fuel Octane Number RON13091
Oil GradeAPI SJ EC or ILSAC
*: California Specification Models
NEW FEATURES Ð 5S-FNE ENGINE 16
6. Fuel Filter
Mounted below the vehicle floor, the fuel filter re-
moves any moisture or oil from the fuel.
7. Fuel Pressure Regulator
The fuel pressure regulator regulates the fuel pressure by reducing the pressure of the compressed natural
gas from the fuel tank to the fuel injection pressure, which is 8 km/cm
2 (114 psi, 785 kPa).
Similar to the fuel shutoff valve for the fuel tank, a fuel shutoff valve is provided on the fuel inlet side
of the fuel pressure regulator to shut off the supply of fuel when the engine is stopped or during abnormal
conditions.
An oil separator that traps the moisture and oil in the fuel is provided on the low pressure side.
A built-in relief valve is provided to protect the parts located on the low pressure side.
While the fuel pressure is being reduced by the fuel pressure regulator, the Joule-Thomson effect associat-
ed with the expansion of the gas causes the fuel pressure regulator to be cooled excessively, exerting
unfavorable influence on the rubber parts such as diaphragms and fuel hoses.
Therefore, to raise the gas temperature, a water passage is provided in the fuel pressure regulator to
allow the engine coolant to warm the regulator.
Oil
Separator
Water Passage
Fuel
Shutoff
Valve
Relief Valve
167CN24 167CN25167CN10
NF
NEW FEATURES Ð 5S-FNE ENGINE19
ENGINE CONTROL SYSTEM
1. General
An engine control system based on the 5S-FE engine has been adopted. The knock sensor has been discontin-
ued because natural gas has a high octane value and is less susceptible to knocking.
The engine control system of 5S-FNE and 5S-FE engines are compared below.
System
Outline5S-FNE5S-FE
SFI
Sequential
A D-type SFI system is used, which indirectly detects
intake air volume by manifold absolute pressure sensor.
Sequential
Multiport Fuel
Injection
The fuel injection system is a sequential multiport fuel
injection system.
Ignition timing is determined by the ECM based on sig-
nals from various sensors.
ESA
Electronic Spark
AdvanceThe ECM corrects the ignition timing in response to en-
gine knocking in accordance with the signals received
from the knock sensor.
Ð
Advance
Torque control correction during gear shifting had been
used to minimize the shift shock.*1
IAC
(Idle Air Control)A rotary solenoid type IAC valve controls the fast idle
and idle speeds.
(1-Coil Type
Built-in Driver)(2-Coil Type)
Fuel Pump ControlFuel pump operation is controlled by signal from the
ECM.Ð
Fuel Cut-Off
Control
The fuel shutoff valves for the fuel tank, fuel pressure
regulator, and delivery pipe are shut off to stop the sup-
ply of fuel when the ignition switch is turned OFF or
during abnormal conditions (such as engine stalling,
SRS airbag deployed, etc.).
Ð
Oxygen Sensor
and Air Fuel Ratio
Sensor
Heater ControlMaintains the temperature of the oxygen sensor and air
fuel ratio sensor at an appropriate level to increase accu-
racy of detection of the oxygen concentration in the ex-
haust gas.
*2
EGR Cut-Off
ControlCuts off EGR according to the engine condition to
maintain drivability of the vehicle and durability of the
EGR components.
Evaporative
Emission ControlThe ECM controls the purge flow of evaporative emis-
sions (HC) in the charcoal canister in accordance with
engine conditions.
Ð
Air Conditioning
Cut-Off ControlBy turning the air conditioning compressor ON or OFF
in accordance with the engine condition, drivability is
maintained.
*3*3
When the ECM detects a malfunction, the ECM diag-
noses and memorized the failed section.
DiagnosisThe diagnosis system includes a function that detects a
malfunction in the evaporative emission control sys-
tem.
Ð
Fail-Safe
When the ECM detects a malfunction, the ECM stops
or controls the engine according to the data already
stored in memory.
*1: Only for Automatic Transaxle Model
*
2: Air fuel ratio sensor only for California specification model.
*
3: The air conditioning magnet clutch controled by the ECM
NEW FEATURES Ð 5S-FNE ENGINE
(Continued)
PIM
NE
G
THW
THA
VTA
AF
#10+
#20
#30
#40
IGT1,
IGT2
IGF
RSD
EGR
OX2
HTAF
HT2
MGC
FUEL W
PSW
ELS
NSW
F/PS
A/C SW
ECM
STA
SPD
R,2,L
STP
#40+ #30+ #20+ #10
FUEL
20
2. Construction
The configuration of the engine control system in the 5S-FNE engine is as shown in the following chart.
SENSORS
MANIFOLD ABSOLUTE
PRESSURE SENSOR
CRANKSHAFT POSITION
SENSOR
CAMSHAFT POSITION
SENSOR
ENGINE COOLANT TEMP.
SENSOR
INTAKE AIR TEMP. SENSOR
THROTTLE POSITION SENSOR
IGNITION SWITCH
COMBINATION METER
wVehicle Speed Signal
AIR FUEL RATIO SENSOR
(Bank 1, Sensor 1)
HEATED OXYGEN SENSOR
(Bank 1, Sensor 2)
POWER STEERING OIL
PRESSER SWITCH
TAILLIGHT & REAR WINDOW
DEFOGGER SYSTEM
PARK/NEUTRAL POSITION
SWITCH
STOP LIGHT SWITCH
AIR CONDITIONING SWITCH
AIRBAG SENSOR ASSEMBLY
wFuel Cut-Off Signal
ACTUATORS
SFI
No. 1 INJECTOR
No. 2 INJECTOR
No. 3 INJECTOR
No. 4 INJECTOR
ESA
IGNITERS and
IGNITION COILS
SPARK PLUGS
IAC
CONTROL VALVE
EGR
VSV
AIR FUEL RATIO SENSOR
HEATER CONTROL
AIR FUEL RATIO SENSOR
HEATER
OXYGEN SENSOR HEATER
CONTROL
HEATED OXYGEN SENSOR
HEATER
AIRE CONDITIONING
CUT-OFF CONTROL
MAGNET CLUTCH RERAY
FUEL GAGE
LOW FUEL LEVEL WARNING
LIGHT
G
Position of Parts in Engine Compartment
[1MZ±FE]
I 1 Idle Air Control Valve
I 2 Igniter
I 5 Ignition Coil No.1
I 6 Ignition Coil No.2
I 7 Ignition Coil No.3
I 8 Injector No.1
I 9 Injector No.2
I 10 Injector No.3
I 11 Injector No.4
I 12 Injector No.5
I 13 Injector No.6
K 1 Knock Sensor 1
K 2 Knock Sensor 2
M 2 Mass Air Flow Meter
N 1 Noise Filter (Ignition)
O 1 Oil Pressure SW
P 1 Park/Neutral Position SW,A/T Indicator Light SW and
Back±Up Light SW
P 2 Power Steering Oil Pressure SWR 1 Radiator Fan Motor
S 1 Starter
S 2 Starter
T 1 Theft Deterrent Horn
T 2 Throttle Position Sensor
V 2 Vehicle Speed Sensor (Combination Meter)
V 3 Vehicle Speed Sensor
(Electronically Controlled Transmission)
V 4 VSV (EGR)
V 5 VSV (EVAP)
V 6 VSV (Intake Air Control)
W 1 Washer Level Warning SW
W 2 Washer Motor
W 3 Water Temp. Sender
W 4 Water Temp. SW No.1
W 5 Water Temp. SW No.2
COMBINATION METER
B2 BRAKE FLUID LEVEL WARNING SW
1±2 : Closed with the float down
C8 (A), C9 (B), C10 (C)
COMBINATION METER
(B) 2±GROUND : Approx. 12 volts with the ignition SW at ST position and the shift lever at P or N position (A/T)
Approx. 12 volts with the ignition SW at ST position and the clutch pedal depressed (M/T)
(A) 13, (C) 7±GROUND : Approx. 12 volts with the ignition SW at ON position
(B)11, (B) 12±GROUND: Always approx. 12 volts
(A) 2, (B) 9, (B) 16, (C) 5±GROUND : Always continuity
O1 OIL PRESSURE SW
1±GROUND : Closed with the oil pressure above approx. 20 kpa (2.8 psi, 0.2 kgf/cm
2)
P3 PARKING BRAKE SW
1±GROUND : Closed with the parking brake lever pulled up
W3 WATER TEMP. SENDER
1±GROUND : Approx. 160±240 W (50°C, 122°F)
Approx. 17.1±21.2 W (120°C, 248°F)
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
B226 (1MZ±FE)J531O129 (5S±FE)B228 (5S±FE)J7A31P127 (1MZ±FE)
C730J8B31P129 (5S±FE)
C8A30J1131P331
C9B30J1531R731
C10C30J1631V227 (1MZ±FE)
D6A30J2131V229 (5S±FE)D6B30J2431W127 (1MZ±FE)
D1030J2831W129 (5S±FE)
F1432J2931W327 (1MZ±FE)
J231J3031W329 (5S±FE)
J431O127 (1MZ±FE)
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CodeSee PageJunction Block and Wire Harness (Connector Location)
1D20Instrument Panel Wire and Instrument Panel J/B (Lower Finish Panel)1G20Instrument Panel Wire and Instrument Panel J/B (Lower Finish Panel)
1J20Cowl Wire and Instrument Panel J/B (Lower Finish Panel)
1T20Instrument Panel Wire and Instrument Panel J/B (Lower Finish Panel)
1W20Cowl Wire and Instrument Panel J/B (Lower Finish Panel)
2J22Cowl Wire and Engine Room J/B No.2 (Engine Compartment Left)
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CodeSee PageJoining Wire Harness and Wire Harness (Connector Location)
IF240Floor Wire and Instrument Panel Wire (Left Kick Panel)
IG140Instrument Panel Wire and Cowl Wire (Lower Finish Panel)IG240Instrument Panel Wire and Cowl Wire (Lower Finish Panel)
IG340Instrument Panel Wire and Cowl Wire (Under The Blower Motor)
II242Engine Wire and Cowl Wire (Under the Blower Motor)
IJ142Engine Wire and Instrument Panel Wire (Under the Blower Motor)
IK242Engine Room Main Wire and Cowl Wire (Right Kick Panel)
SERVICE HINTS