IGNITION SYSTEM
ENGINE ELECTRICAL16-30
IGNITION SYSTEM
GENERAL INFORMATIONM1163000100294
This system is equipped with two ignition coils (A and
B) with built-in power transistors for the No. 1 and
No. 4 cylinders and the No. 2 and No. 3 cylinders
respectively.
Interruption of the primary current flowing in the pri-
mary side of ignition coil A generates a high voltage
in the secondary side of ignition coil A. The high volt
-
age thus generated is applied to the spark plugs of
No. 1 and No. 4 cylinders to generate sparks. At the
time that the sparks are generated at both spark
plugs, if one cylinder is at the compression stroke,
the other cylinder is at the exhaust stroke, so that
ignition of the compressed air/fuel mixture occurs
only for the cylinder which is at the compression
stroke.
In the same way, when the primary current flowing in
ignition coil B is interrupted, the high voltage thus
generated is applied to the spark plugs of No. 2 and
No. 3 cylinders.
The engine-ECU
turns the two power transistors inside the ignition
coils alternately on and off. This causes the primary
currents in the ignition coils to be alternately inter
-
rupted and allowed to flow to fire the cylinders in the
order 1-3-4-2.
The engine-ECU
determines which ignition coil should be controlled
by means of the signals from the camshaft position
sensor which is incorporated in the camshaft and
from the crank angle sensor which is incorporated in
the crankshaft. It also detects the crankshaft position
in order to provide ignition at the most appropriate
timing in response to the engine operation condi
-
tions. It also detects the crankshaft position in order
to provide ignition at the most appropriate timing in
response to the engine operation conditions.
When the engine is cold or operated at high alti-
tudes, the ignition timing is slightly advanced to pro-
vide optimum performance.
When the automatic transmission shifts gears, the
ignition timing is also retarded in order to reduce out
-
put torque, thereby alleviating shifting shocks.
SYSTEM DIAGRAM
AK101074
Air flow sensor
<4G6> MAP sensor <4G1>
Intake air temperatur
sensor
Engine coolant
temperature sensor
Camshaft position
sensor
Crank angle sensor
Barometric pressure
sonsor <4G6>
Detonatoin sensor
Ignition switch-ST Engine-A/T-
ECU Engine-ECU
Ignition coil B
Cylinder No. 23 4
AG
1
Spark plug Ignition coil A
Ignition
switch
Battery
IGNITION SYSTEM
ENGINE ELECTRICAL16-34
STANDARD WAVEFORM
Observation Conditions
FunctionSecondary
Pattern heightHigh (or Low)
Pattern selectorRaster
Engine revolutionsCurb idle speed
AKX00278
kV0
Secondary
ignition voltage
wave pattern
Ignition voltage
(point D)
Spark line (point A)
Dwell section Wave dampling reduction section (point B)
Point C Time
AD
IGNITION SYSTEM
ENGINE ELECTRICAL16-35
Observation Conditions (The only change from above condition is the pattern selector.)
Pattern selectorDisplay
AKX01275
kV
Secondary ignition
voltage wave pattern 0
2NO. 1 cylinder
NO. 3 cylinder
ignition noise
Newtral section NO. 4 cylinder
NO. 2 cylinder
ignition noise
Time
AC
WA VEFORM OBSER V A T ION POINTS
Point A: The he ight, len g th and s l ope of th e sp a r k line sho w the following trends (Re f er to abnorma l
wave
form exam ples, 1 , 2, 3 a nd 4).
Spark linePlug gapCondition of
electrodeCompression
force Concentration
of air mixtureIgnition
timingSpark plug
cable
LengthLongSmallNormalLowRichAdvancedLeak
ShortLargeLarge wearHigh LeanRetardedHigh
resistance
HeightHighLargeLarge wearHighLeanRetardedHigh
resistance
LowSmallNormalLow RichAdvancedLeak
SlopeLargePlug is fouled−−−−
Point B: Number of v i bra t ion in red uction vi bra t ion sec tion (Refer to a bnormal wavefo r m examp l e 5)
Number of vibrationsCoil and condenser
3 or moreNormal
Except aboveAbnormal
Point C: Number of v i bra t ions a t beginnin g of dwell se ction (Refer to a bnormal wave form exam ple 5)
Number of vibrationsCoil
5 − 6 or higherNormal
Except aboveAbnormal
Point D: Ignition volt a g e height (distribution per each cylinder) s hows the follo wing tren ds.
Ignition
voltagePlug gapCondition of
electrodeCompression
forceConcentration
of air mixtureIgnition
timingSpark plug
cable
HighLargeLarge wearHighLeanRetardedHigh
resistance
LowSmallNormalLowRichAdvancedLeak
EMISSION CONTROL
ENGINE AND EMISSION CONTROL17-11
2. Plug the nipple from which the vacuum hose was removed.
3. When the engine is cold or hot, apply a vacuum of 53 kPa, and check the condition of the vacuum.
When engine is cold
(Engine coolant temperature: 40°C or less)
Engine conditionNormal condition
At idleVacuum is maintained.
3,000 r/min
When engine is hot
(Engine coolant temperature: 80°C or higher)
Engine conditionNormal condition
At idleVacuum is maintained.
3,000 r/min (within 3
minutes after engine
starts)Vacuum will leak.
PURGE PORT VACUUM CHECKM1173001500177
AK300773
<4G1>
AB
Plug
Vacuum hose
AK300774
<4G6>
AB
Plug
Vacuum hose
1.Disco nnect th e vacuum ho se (red st ripe) from the
throttle body and connect a hand vacuum pump to
th e nip p le.
2.Plu g the vacuum hose (red stripe).
AK100011AC
Vac-
uum
Engine speed (r/min)
3.S t art the engine.
4.Check t hat a f a irly co nst ant n egative p r essure is
g enerate d regard l ess of the en gine spee d.
5.If no neg ative pressur e is genera t ed, th e port is
p r obably blocked an d sh ould be cleane d.
PURGE CONTROL SOLENOID VA L V E
CHECK
M1173 0017 0019 3
NOTE: Whe n discon nect i ng th e va cuum hose,
always make a mark so th at it can be reconnected at
original p o sition.
AK100012AC
Battery
A
AK100013
1.
Disco nnect the vacu um h o se f r om th e solenoid
valve.
2.Disco nnect the ha rness connector .
3.Con nect a ha nd vacu um pump to nipp le (A) of the
solen o id valve (ref e r to th e ill ust r ation at le f t ).
4.Check a i rtig htness b y app lying a vacuum with
volt age applied d i rectly from t he batt e ry to the
p u rge con t rol so leno id valve an d without app lying
volt age .
Battery voltageNormal condition
AppliedVacuum leaks
Not appliedVacuum maintained
EMISSION CONTROL
ENGINE AND EMISSION CONTROL17-12
5. Measure the resistance between the terminals of the solenoid valve.
Standard value: 30 − 34 Ω (at 20°C)
FUEL VAPOUR CANISTER RE MOVAL AND INSTALLATION
M1173004200153
Pre-removal and Post-installation Operation
Air Cleaner Assembly Removal and Installation (Refer to
GROUP 15
P.15-3).
AC208253
1
2
3
4 5 6
7 8
AD
Removal steps
1.Emission vacuum hose connection
2.Fuel vapour control line hose
3.Fuel vapour control check valve
4.Fuel vapour control line hose
5.Fuel vapour control line clamp
6.Fuel vapour canister
7.Fuel high-pressure hose clamp
8.Fuel vapour canister bracket
EXHAUST GAS RECIRCULA
T ION
(EGR) SYSTEM
GENERAL INFORMAT ION (EGR SYSTEM)
M1173 0052 0032 7
The exhaust gas recircu l atio n (EGR) system lowers
the nitrogen
oxide (NOx) emission level.
When the air/fuel mixture combus tio n temp erature is
high,
a larg e qua ntity of nitrogen oxides (NOx) is
generat
ed in the comb ustion chamb e r .
Therefor e, this syst em re circulat es p a rt o f emission
gas fro
m the e x ha ust po rt of the cylinder h ead to th e
combust
i on chamber thro ugh th e int a ke ma nifold to
decre
ase the air/fuel mixture combust i on te mpera
-
ture, resulting in redu ctio n of NOx.
The EGR flow rate is cont rolle d by the EGR valve so
as no
t to de crease the driveability .
OPERAT ION
The EGR valve is being clos ed an d does not re circu-
late ex hau st ga ses unde r one o f the fo llo wing condi-
tions.
Otherwise, th e EGR va lve is opene d an d recircul ates
exha
ust g a ses.
•The engine coolan t temperature is low .
•The engine is at idle.
•The throttle va lve is widely ope ned.
EMISSION CONTROL
ENGINE AND EMISSION CONTROL17-15
EGR SYSTEM CHECK
M1173002600348
AK300780AB
<4G1>
EGR valve
Green stripe
Three-way
terminal
AK300781AB
<4G6>
EGR valve
Green stripe
Three-way
terminal
1.Disco nnect the vacu um ho se (Green stripe) from
th e EGR valve, a nd th en connect a hand vacuum
pu mp via t he thre e-way te rmin al.
2.Wh en the engine is hot o r cold, check the
condition of va cuum by racing the engine.
When engine is c o ld
(Eng ine coo lant tem perature: 20°C or less)
Throttle valveNormal vacuum co ndition
Open quicklyNo va cuum will gene rate (th e
same as baro
m etric pre s sure.)
When engine is h o t
(Eng ine coo lant tem perature: 80°C or higher)
Throttle valveNormal vacuum c ondition
Open quicklyIt will mo me nt a r i l y rise o v er 13
kPa
3.Disco nnect the th ree-way t e rminal.
AK300782AB
<4G1>
EGR valve
Green stripe
AK300783AB
<4G6>
EGR valve
Green stripe
4.Conn ect the han d va cuum pump to t he EGR
valve nipple.
5.Check whe t her th e engine st alls or the idling is
u n st able when a vacuum of 30 kPa or h i gher is
a pplied during idling.
EGR V A L V E CHECKM1173 0028 0022 3
1.Remove the EGR valve an d inspect for stickin g ,
carbon deposit s, e t c. If found , clean with a
suit able so lve n t so that th e va lve seat s corre ctly .
2.Conn ect a hand vacuum pump to the EGR va lve .
3.App l y 6 7 kPa of va cuum, and check t hat the
vacu um is maint a ined.
AKX00348
4.App l y a vacuum and chec k th e p a ssage of air by
b l owing throug h one side of the EGR p a ssage.
VacuumPassage of air
5.3 kPa or lessAir is not blown out
27 kPa or moreAir is blown out
EMISSION CONTROL
ENGINE AND EMISSION CONTROL17-16
5. Replace the gasket, and tighten to the specified torque.
Tightening torque:
<4G1> 21 ± 4 N⋅m
<4G6> 20 ± 2 N⋅m
EGR PORT VACUUM CHECK <4G1>M1173002900167
AK300784AB
Green strip
1.Disco nnect the vacu um ho se (Green stripe) from
th e t h ro tt le b o d y EGR va cuu m ni pp le an d co nn ec t
a hand vacu um p u mp to the nipple.
2.Plu g the vacuum hose (Gree n stripe).
AK201224AB
Vac-
uum
Engine speed (r/min)
3.S t art the engin e and check t hat, af ter ra ising th e
engine spe ed by ra cin g the e ngine, p u rge vacuu m
raises according to engine speed.
NOTE: If ther e is a prob lem with change in vac-
uum, the t h rottle bod y p u rge port may be clo gged
an
d requ ire clean ing.
EGR PORT VA CUUM CHECK <4G6>M1173 0029 0015 6
AK300786AB
White stripe
1.Disco nnect the vacu um h o se (W hite strip e ) from
th e t h ro tt le b o d y EGR va cuu m ni pp le an d co nn ec t
a hand vacuum p u mp to the nipple.
2.Plug the vacuum hose (White stripe).
AK100011AC
Vac-
uum
Engine speed (r/min)
3.S t art the engine.
4.Check that a fairly const a nt n egative is gene rated
re gardle s s of the engine sp eed.
5.If no neg ative pressur e is genera t ed, th e port is
p r obably blocked an d sh ould be cleane d.
EGR CONTROL SOLENOID VA L V E
CHECK <
4 G1 >
M1173 0031 0023 8
NOTE: Whe n discon nect i ng th e va cuum hose,
always make a mark so th at it can be reconnected at
original p o sition.
AKX00351
A
B
AE
Battery
1. Disco nnect the vacu um h o se f r om th e solenoid
valve.
2.Disco nnect the ha rness connector .
3.Con nect a ha nd vacu um pump to nipp le (A) of the
solen o id valve (ref e r to th e ill ust r ation at le f t ).
4.Check a i r tightness b y ap plying a vacuum with
volt age applied d i rectly from t he batt e ry to the
EGR cont rol solen o id valve and withou t applyin g
volt age .
Battery voltageNormal condition
AppliedVa c u u m l e a k s
Not appliedVacuum maintained
AKX00352
EMISSI ON CONTROL
ENGINE AND E M ISSION CON T R O L17-17
5.Measure the resist ance between the te rmin als of
th e solenoid va lve .
St andard va lue: 29 − 35 Ω (at 20°C)
EGR CONTROL SOLENOID V A L V E
CHECK <
4 G6>
M1173 0031 0024 9
NOTE: Whe n discon nect i ng th e va cuum hose,
always
make a mark so th at it can be reconnected at
original p o sition.
AK201251AB
A
B
C
Battery
1.Disco nnect the vacu um h o se f r om th e solenoid
valve.
2.Disco nnect the ha rness connector .
3.Con nect a ha nd vacu um pump to nipp le (A) of the
solen o id valve (ref e r to th e ill ust r ation at le f t ).
4.Check a i r tightness b y ap plying a vacuum with
volt age applied d i rectly from t he batt e ry to the
EGR cont rol solen o id valve and withou t applyin g
volt age .
Battery
voltageB nipple
conditionNormal condition
Not appliedOpenVacuum
maintained
AppliedOpenVacuum leaks
ClosedVacuum
maintained
AK100016
5.Measure the resist ance betwee n the te rminals of
th e so lenoid valve .
St andard va lue: 29 − 35 Ω (at 20°C)