Page 68 of 364
BASE ENGINE
ENGINE MECHANICAL <4A9>11A-20
VA LV E G U I D E
AK305053
d
AB
Dh
The in
t a ke an d exhaust valves use the same -design
valve gu
ide.
ItemIntake
D (Outer diameter) mm10.5
d (Inner diameter) mm4.5
h (height) mm34.5
CYLINDER HEAD GASKET
AK305054AB
Water hole
Oil hole
Water hole
Th e met a l g a sket having he at resist ance, sea l ability
and low cost is use
d for th e cylin der hea d gasket .
CYLINDER HEAD COVER
AK402398AC
Cylinder head cover
A resin cylin der hea d co ver is used fo r the cylinder head.
Page 77 of 364
BASE ENGINE
ENGINE MECHANICAL <4A9>11A-29
VALVE MECHANISM
AK305076AB
Exhaust valveIntake valve
Exhaust camshaft
Intake camshaft
Spark plug guide
Valve tappet
The valve mechanism is based on a 4-va lve DOHC
(Do
uble Over Head Camsha f t ) d e sign having the
camshaf
t on the u pper valve. Each cylin der has 2
int
a ke valves and 2 exh aust valves, arrang ed in a
V
- shape p a ttern.Camsh a f t rot a tion is transmitte d via va lve t a ppet s to
the respective
valves which ope n and close accord
-
ingly.
VALV E
AK305078
d
d
DD
L
Intake
Exhaust
L
AB
The valves ha ve h eat-resist an ce. Th e entire valve
surface is trea
ted with gas nitriding.ItemIntake valveExhaust valve
Head diameter
mm30.525.5
Stem diameter
mm5.05.0
Overall length
mm89.6190.94
Page 80 of 364

BASE ENGINE
ENGINE MECHANICAL <4A9>11A-32
CAMSHAFT
AK304999
Intake camshaft
Exhaust camshaft
AB
Hollow section
Advance
oil channel
Retard
oil channel
Cam positon sensing ring
Dowel pinSealing cap
The lightweight camshaf t is ach i eved by the h o llo w
design.
Oil channels run through the int a ke camshaf t,
through
wh ich oil is sent from t he oil fee der co ntrol
valve to
the V . V . T . sprocket.
A cam position sen s in g ring is press-fitt ed onto the
rear port
i on o f the int a ke camshaf t.
ItemDimension
Overall length
mmIntake407.5
Exhaust361.9
Journal mm26
Valve lift mmIntake8.4
Exhaust7.9
OIL FEEDER CONT ROL V A L V E(OCV)
AK302997AB
Spring guideValve sleeve
Plunger spring Spool
O-ring
Insulation coilar
StatorGuide cap Bracket
Yo k eSeal cap
Plunger
Shaft Terminal
Bobbin
Tape
Enameled copper wire
Drain
Drain
Pump
Pressure
chamber
Default
pressure
chamber
The oil fee
der co ntrol valve is essen t ially a solenoid
valve, re
gulat ed by the en gine -ECU or
engin
e -A-M/T -ECU signals to feed o il to the V . V . T .
sprocket
assemb ly t o move the van e rotor .
Page 89 of 364

GENERAL INFORMATION
ENGINE LUBRICATION12-2
GENERAL INFORMATION
M2120000100175
LUBRICATION SYSTEM SCHEMATIC<4A9>
AK402024AC
Oil screenOil pump
Timing chain case
oil passage
Cylinder block
oil passage(right side) Oil filter
Relief valve
Cylinder block
oil passage
(main gallery)Crankshaft
journal
Exhaust camshaft
journal
Oil pressure switch
Cylinder head
oil passage
No.1 Camshaft
journal
Intake camshaft
journal Crankshaft
pin
The lu
brication system of th e 4A9 en gine has a full
pressure de
livery system and a full flow oil filtering
system. The o
il stored in the oil p an is pumped
up/out
by th e oil pump. Af ter the relie f valve regu
-
lates the oil p r essure, th e oil is delivere d to th e cylin-
der block through the o il f ilte r , the o il p a ssag e of the
cylinde
r blo ck a nd the each jou r nal o f the crankshaf t.
The oil del ivered to the ea ch jo urnal of th e cranksh af t
is supplied
to the pin th rough the in ner p a ssage of
the crankshaf
t.
The oil delivered to the cylinder head is supplied t o
the ea
ch journa l of the camshaf t th rough the cylinde r
head.
Page 90 of 364
GENERAL INFORMATION
ENGINE LUBRICATION12-3
LUBRICATION SYSTEM SCHEMATIC<4G1>
AK402151AC
Oil screen
Oil pump
Oil filter
Relief valve
Cylinder block
oil passage
(main gallery)Crankshaft
journal
Exhaust camshaft
journal
Oil pan Oil pressure switch
Cylinder head
oil passage
No.1 Camshaft
journal
Intake camshaft
journal Crankshaft pin
PistonOil jet
Oil cooler
Turbo charger
Lash adjuster Cam
To correspond with the impr oved engine outp u t per-
formance b y emplo y ing the tu rboch a rger , the oil
cooler and
the oil jet are u s ed for 4GI engine.
Page 100 of 364

GENERAL INFORMATION
MULTIPOINT FUEL INJECTION (MPI) <4A9>13A-6
List of Component Functions
NameFunction
ECU
Engine-ECU or engine-CVT-ECU The signals that are input by the sensors enable the
actuators to be controlled in accordance with the
driving conditions.
Sensors
Ignition switch-IGThis signal indicates the ON/OFF condition of the
ignition switch. When this signal is input, the
engine-ECU or engine-CVT-ECU
supplies power to the crank angle sensor, camshaft
position sensor, etc.
Ignition switch-STThis signal indicates that the engine is cranking.
Based on this signal, the engine-ECU or
engine-CVT-ECU controls the fuel injection,
throttle valve position, and the injection timing that
are suited for starting the engine.
Manifold absolute pressure sensor Uses a pressure conversion element to detect the
pressure in the intake manifold, converts it into a
voltage signal, and outputs it to the
engine-ECU or engine-CVT-ECU. The
engine-ECU or engine-CVT-ECU
optimally corrects the fuel injection amount and the
like based on this signal.
Oxygen sensor This sensor, which contains zirconia and platinum
electrodes, detects the level of oxygen concentration
in the exhaust gases. The engine-ECU or
engine-CVT-ECU determines whether the
air-fuel ratio is at the optimal stoichiometric ratio in
accordance with this oxygen concentration level.
Barometric pressure sensorThis sensor detects the altitude of the vehicle. It
enables the engine-ECU or engine-CVT-ECU
to make fuel injection volume corrections in
order to achieve an appropriate air-fuel ratio.
Intake air temperature sensorThis sensor, which contains a thermistor, detects the
temperature of the intake air. The engine-ECU
or engine-CVT-ECU makes fuel injection
volume corrections that suit the intake air
temperature, in accordance with the voltage that is
output by this sensor.
Engine coolant temperature sensorThis sensor, which contains a thermistor, detects the
temperature of the engine coolant. The engine-ECU
or engine-CVT-ECU determines the
warm-up condition of the engine in accordance with
the voltage that is output by this sensor, in order to
control the fuel injection volume, idle speed, and
ignition timing.
Page 109 of 364

DIAGNOSIS SYSTEM
MULTIPOINT FUEL INJECTION (MPI) <4A9>13A-15
P0125*Feedback system monitorOxygen sensor not operatingON
P0130Oxygen sensor (front) systemOpen circuit or short-circuit in
sensor-related circuitsON
P0135Oxygen sensor (front) heater
systemOpen circuit or short-circuit in
heater-related circuitsON
P0136Oxygen sensor (rear) systemOpen circuit or short-circuit in
sensor-related circuitsON
P0141Oxygen sensor (rear) heater
systemOpen circuit or short-circuit in
heater-related circuitsON
P0170Abnormal fuel systemLeanness or richness problemON
P0201No.1 injector systemOpen circuit or short-circuit in
injector-related circuitsON
P0202No.2 injector systemOpen circuit or short-circuit in
injector-related circuitsON
P0203No.3 injector systemOpen circuit or short-circuit in
injector-related circuitsON
P0204No.4 injector systemOpen circuit or short-circuit in
injector-related circuitsON
P0222*Throttle position sensor (sub)
circuit low inputOpen circuit or short-circuit in
sensor-related circuitsON
P0223*Throttle position sensor (sub)
circuit high inputOpen circuit in sensor-related
circuitsON
P0300*Random/multiple cylinder misfire
detectedMisfiringON
P0301*No.1 cylinder misfire detectedMisfiringON
P0302*No.2 cylinder misfire detectedMisfiringON
P0303*No.3 cylinder misfire detectedMisfiringON
P0304*No.4 cylinder misfire detectedMisfiringON
P0325Detonation sensor systemAbnormal sensor outputON
P0335Crank angle sensor systemAbnormal sensor outputON
P0340Camshaft position sensor systemAbnormal sensor outputON
P0403 Exhaust gas recirculation control
systemOpen circuit or short-circuit in
valve-related circuitsON
P0421Warm up catalyst malfunctionAbnormal exhaust gas purification
performance of catalystON
P0443Purge control solenoid valve
systemOpen circuit or short-circuit in
solenoid valve-related circuitsON
P0500 Vehicle speed sensor systemOpen circuit or short-circuit in
sensor-related circuitsON
P0513Immobilizer malfunctionOpen circuit or short-circuit in
sensor-related circuits−
P0603EEP ROM malfunctionAbnormality in engine-ECU
or engine-CVT-ECU −
Code No. Diagnosis item Main diagnosis contents Engine
warning lamp
Page 111 of 364

DIAGNOSIS SYSTEM
MULTIPOINT FUEL INJECTION (MPI) <4A9>13A-17
DATA LIST FUNCTION
The data list items are given in the table below
Item No.Inspection itemUnit
11Oxygen sensor (front)mV
13Intake air temperature sensor°C
14Throttle position sensor (sub)mV
16Power supply voltageV
18Cranking signal (ignition switch-ST)ON/OFF
21Engine coolant temperature sensor°C
22Crank angle sensorr/min
25Barometric pressure sensorkPa
29Inhibitor switchP or N/D, DS, L, or R
32Manifold absolute pressure sensorkPa
41Injectorsms
44Ignition advanceBTDC
49A/C relayON/OFF
59Oxygen sensor (rear)mV
67Stop lamp switchON/OFF
68Exhaust gas recirculation valveSTEP
77Accelerator pedal position sensor (sub)mV
78Accelerator pedal position sensor (main)mV
79Throttle position sensor (main)mV
7EVariable valve timing phase angleCA
13*Intake air temperature sensor°C
21*Engine coolant temperature sensor°C
22*Crank angle sensorr/min
24*Vehicle speed sensorkm/h
32*Manifold absolute pressure sensorkPa
44*Ignition advancedeg
81*Long-term fuel compensation%
82*Short-term fuel compensation%
87*Calculated load value%
88*Fuel control conditionOpen loopOL
Closed loopCL
Open loop owing to drive
conditionOL-DRV
Open loop owing to system
malfunctionOL-SYS
Closed loop based on one
oxygen sensorCL-HO2S