air condition MITSUBISHI LANCER 2005 User Guide
Page 32 of 788
TROUBLESHOOTING
ENGINE COOLING14-18
Q: Are these connectors in good condition?
YES :
Go to Step 5 .
NO : Repair or replace the connector. Then go to
Step 8 .
STEP 5. Check the harness wire between cooling
fan motor drive control unit connector A-18
terminal 2 and engine-ECU connector C-123
terminal 21 <M/T> or engine-A/T-ECU connector
C-122 terminal 18 <A/T>.
Q: Are these harness wires in good condition?
YES :
Go to Step 6 .
NO : Repair the damaged harness wire. Then go
to Step 8 .
AC303555AB
Connector: C-123 <M/T>, C-122 <A/T>
C-123 <M/T>
or
C-122 <A/T>
C-123 <M/T>
Engine-ECU <M/T> or
engine-A/T-ECU <A/T>
C-122 <A/T>
AC100293
A-18
321
Connector: A-18
AD
AC303555AB
Connector: C-123 <M/T>, C-122 <A/T>
C-123 <M/T>
or
C-122 <A/T>
C-123 <M/T>
Engine-ECU <M/T> or
engine-A/T-ECU <A/T>
C-122 <A/T>
Page 94 of 788
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
primary side of ignition coil A generates a high
voltage in the secondary side of ignition coil A. The
high voltage 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 <M/T> or engine-A/T-ECU <A/T>
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
interrupted and allowed to flow to fire the cylinders in
the order 1-3-4-2.
The engine-ECU <M/T> or engine-A/T-ECU <A/T>
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
conditions. 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
altitudes, the ignition timing is slightly advanced to
provide optimum performance.
When the automatic transmission shifts gears, the
ignition timing is also retarded in order to reduce
output 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-STEngine-A/T-
ECU <A/T> Engine-ECU
<M/T>Ignition coil B
Cylinder No.
23 4
AG
1 Spark plugIgnition coil AIgnition
switch
Battery
Page 99 of 788
IGNITION SYSTEM
ENGINE ELECTRICAL16-35
WAVEFORM OBSERVATION POINTS
Point A: The height, length and slope of the spark line show the following trends (Refer to abnormal
waveform examples, 1, 2, 3 and 4).
Point B: Number of vibration in reduction vibration section (Refer to abnormal waveform example 5)
Point C: Number of vibrations at beginning of dwell section (Refer to abnormal waveform example 5)
Point D: Ignition voltage height (distribution per each cylinder) shows the following trends.
AKX01275
kV
Secondary ignition
voltage wave pattern
0
2NO. 1 cylinder
NO. 3 cylinder
ignition noise
Newtral sectionNO. 4 cylinderNO. 2 cylinder
ignition noise
Time
AC
Spark line Plug gap Condition of
electrodeCompression
force Concentration
of air mixtureIgnition
timingSpark plug
cable
Length Long Small Normal Low Rich Advanced Leak
Short Large Large wear High Lean Retarded High
resistance
Height High Large Large wear High Lean Retarded High
resistance
Low Small Normal Low Rich Advanced Leak
Slope Large Plug is fouled
−− −−
Number of vibrations Coil and condenser
3 or more Normal
Except above Abnormal
Number of vibrations Coil
5 − 6 or higher Normal
Except above Abnormal
Ignition
voltagePlug gap Condition of
electrodeCompression
forceConcentration
of air mixtureIgnition
timingSpark plug
cable
High Large Large wear High Lean Retarded High
resistance
Low Small Normal Low Rich Advanced Leak
Page 116 of 788
EMISSION CONTROL <MPI>
ENGINE AND EMISSION CONTROL17-8
VACUUM HOSE CHECKM1173007300159
1. Using the piping diagram as a guide, check to be
sure that the vacuum hoses are correctly
connected.
2. Check the connection condition of the vacuum
hoses, (removed, loose, etc.) and check to be
sure that there are no bends or damage.
VACUUM HOSE INSTALLATIONM1173007200107
1. When connecting the vacuum hoses, they should
be securely inserted onto the nipples.
2. Connect the hoses correctly, using the vacuum
hose piping diagram as a guide.
CRANKCASE EMISSION CONTROL
SYSTEM
GENERAL INFORMATION (CRANKCASE
EMISSION CONTROL SYSTEM)
M1173005000237
The crankcase emission control system prevents
blow-by gases from escaping inside the crankcase
into the atmosphere.
Fresh air is sent from the air cleaner into the
crankcase through the breather hose.
The air becomes mixed with the blow-by gases
inside the crankcase.
The blow-by gas inside the crankcase is drawn into
the intake manifold through the positive crankcase
ventilation (PCV) valve.
The PCV valve lifts the plunger according to the
intake manifold vacuum so as to regulate the flow of
blow-by gas properly.
In other words, the blow-by gas flow is regulated
during low load engine operation to maintain engine
stability, while the flow is increased during high load
operation to improve the ventilation performance.
SYSTEM DIAGRAM
AK204365
Air cleaner
Air
Ventilation hose
Breather hose
PCV valve
AB
Page 119 of 788
EMISSION CONTROL <MPI>
ENGINE AND EMISSION CONTROL17-11
1. Disconnect the vacuum hose (red stripe) from
throttle body and connect it to a hand vacuum
pump.
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)
When engine is hot
(Engine coolant temperature: 80°C or higher)
PURGE PORT VACUUM CHECKM1173001500177
1. Disconnect the vacuum hose (red stripe) from the
throttle body and connect a hand vacuum pump to
the nipple.
2. Plug the vacuum hose (red stripe).3. Start the engine.
4. Check that a fairly constant negative pressure is
generated regardless of the engine speed.
5. If no negative pressure is generated, the port is
probably blocked and should be cleaned.
PURGE CONTROL SOLENOID VALVE
CHECK
M1173001700193
NOTE: When disconnecting the vacuum hose,
always make a mark so that it can be reconnected at
original position.
1. Disconnect the vacuum hose from the solenoid
valve.
2. Disconnect the harness connector.
3. Connect a hand vacuum pump to nipple (A) of the
solenoid valve (refer to the illustration at left). Engine condition Normal condition
At idle Vacuum is maintained.
3,000 r/min
Engine condition Normal condition
At idle Vacuum is maintained.
3,000 r/min (within 3
minutes after engine
starts)Vacuum will leak.
AK300773
<4G1>
AB
Plug
Vacuum hose
AK300774
<4G6>
AB
Plug
Vacuum hose
AK100011AC
Vac-
uum
Engine speed (r/min)
AK100012AC
Battery A
AK100013
Page 120 of 788
EMISSION CONTROL <MPI>
ENGINE AND EMISSION CONTROL17-12
4. Check airtightness by applying a vacuum with
voltage applied directly from the battery to the
purge control solenoid valve and without applying
voltage.
5. Measure the resistance between the terminals of
the solenoid valve.
Standard value: 30 − 34 Ω (at 20°C)
FUEL VAPOUR CANISTER REMOVAL
AND INSTALLATION
M1173004200153
Battery voltage Normal condition
Applied Vacuum leaks
Not applied Vacuum maintained
Pre-removal and Post-installation Operation
Air Cleaner Assembly Removal and Installation (Refer to
GROUP 15 P.15-3).
AC208253
1 2 3
4
56
78
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 hose5. Fuel vapour control line clamp
6. Fuel vapour canister
7. Fuel high-pressure hose clamp
8. Fuel vapour canister bracketRemoval steps (Continued)
Page 121 of 788
EMISSION CONTROL <MPI>
ENGINE AND EMISSION CONTROL17-13
EXHAUST GAS RECIRCULATION
(EGR) SYSTEM
GENERAL INFORMATION (EGR SYSTEM)M1173005200327
The exhaust gas recirculation (EGR) system lowers
the nitrogen oxide (NOx) emission level.
When the air/fuel mixture combustion temperature is
high, a large quantity of nitrogen oxides (NOx) is
generated in the combustion chamber.
Therefore, this system recirculates part of emission
gas from the exhaust port of the cylinder head to the
combustion chamber through the intake manifold to
decrease the air/fuel mixture combustion
temperature, resulting in reduction of NOx.The EGR flow rate is controlled by the EGR valve so
as not to decrease the driveability.
OPERATION
The EGR valve is being closed and does not
recirculate exhaust gases under one of the following
conditions.
Otherwise, the EGR valve is opened and recirculates
exhaust gases.
•The engine coolant temperature is low.
•The engine is at idle.
•The throttle valve is widely opened.
SYSTEM DIAGRAM
AK300775
Manifold absolute
pressure (MAP) sensor Engine-ECU <M/T>,
Engine-A/T-ECU <A/T>
Engine coolant
temperature sensor
Crank angle sensor EGR
control
solenoid
valve
EGR valveOFF
ON
Control
relay
Battery
AB
<4G1>
Page 123 of 788
EMISSION CONTROL <MPI>
ENGINE AND EMISSION CONTROL17-15
EGR SYSTEM CHECKM1173002600348
1. Disconnect the vacuum hose (Green stripe) from
the EGR valve, and then connect a hand vacuum
pump via the three-way terminal.
2. When the engine is hot or cold, check the
condition of vacuum by racing the engine.
When engine is cold
(Engine coolant temperature: 20°C or less)
When engine is hot
(Engine coolant temperature: 80°C or higher)
3. Disconnect the three-way terminal.4. Connect the hand vacuum pump to the EGR
valve nipple.
5. Check whether the engine stalls or the idling is
unstable when a vacuum of 30 kPa or higher is
applied during idling.
EGR VALVE CHECKM1173002800223
1. Remove the EGR valve and inspect for sticking,
carbon deposits, etc. If found, clean with a
suitable solvent so that the valve seats correctly.
2. Connect a hand vacuum pump to the EGR valve.
3. Apply 67 kPa of vacuum, and check that the
vacuum is maintained.
4. Apply a vacuum and check the passage of air by
blowing through one side of the EGR passage. Throttle valve Normal vacuum condition
Open quickly No vacuum will generate (the
same as barometric pressure.)
Throttle valve Normal vacuum condition
Open quickly It will momentarily rise over 13
kPa
AK300780AB
<4G1>
EGR valve
Green stripe
Three-way
terminal
AK300781AB
<4G6>
EGR valve
Green stripe
Three-way
terminal
Vacuum Passage of air
5.3 kPa or less Air is not blown out
27 kPa or more Air is blown out
AK300782AB
<4G1>
EGR valve
Green stripe
AK300783AB
<4G6>
EGR valve
Green stripe
AKX00348
Page 124 of 788
EMISSION CONTROL <MPI>
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
1. Disconnect the vacuum hose (Green stripe) from
the throttle body EGR vacuum nipple and connect
a hand vacuum pump to the nipple.
2. Plug the vacuum hose (Green stripe).
3. Start the engine and check that, after raising the
engine speed by racing the engine, purge vacuum
raises according to engine speed.
NOTE: If there is a problem with change in
vacuum, the throttle body purge port may be
clogged and require cleaning.
EGR PORT VACUUM CHECK <4G6>M1173002900156
1. Disconnect the vacuum hose (White stripe) from
the throttle body EGR vacuum nipple and connect
a hand vacuum pump to the nipple.
2. Plug the vacuum hose (White stripe).
3. Start the engine.
4. Check that a fairly constant negative is generated
regardless of the engine speed.
5. If no negative pressure is generated, the port is
probably blocked and should be cleaned.
EGR CONTROL SOLENOID VALVE
CHECK <4G1>
M1173003100238
NOTE: When disconnecting the vacuum hose,
always make a mark so that it can be reconnected at
original position.
1. Disconnect the vacuum hose from the solenoid
valve.
2. Disconnect the harness connector.
3. Connect a hand vacuum pump to nipple (A) of the
solenoid valve (refer to the illustration at left).
4. Check air tightness by applying a vacuum with
voltage applied directly from the battery to the
EGR control solenoid valve and without applying
voltage.
AK300784AB
Green strip
AK201224AB
Vac-
uum
Engine speed (r/min)
AK300786AB
White stripe
Battery voltage Normal condition
Applied Vacuum leaks
Not applied Vacuum maintained
AK100011AC
Vac-
uum
Engine speed (r/min)
AKX00351
A
B
AE
Battery
Page 125 of 788
EMISSION CONTROL <MPI>
ENGINE AND EMISSION CONTROL17-17
5. Measure the resistance between the terminals of
the solenoid valve.
Standard value: 29 − 35 Ω (at 20°C)
EGR CONTROL SOLENOID VALVE
CHECK <4G6>
M1173003100249
NOTE: When disconnecting the vacuum hose,
always make a mark so that it can be reconnected at
original position.1. Disconnect the vacuum hose from the solenoid
valve.
2. Disconnect the harness connector.
3. Connect a hand vacuum pump to nipple (A) of the
solenoid valve (refer to the illustration at left).
4. Check air tightness by applying a vacuum with
voltage applied directly from the battery to the
EGR control solenoid valve and without applying
voltage.
5. Measure the resistance between the terminals of
the solenoid valve.
Standard value: 29 − 35 Ω (at 20°C)
AKX00352
AK201251AB
A
B
C
Battery
Battery
voltageB nipple
conditionNormal condition
Not applied Open Vacuum
maintained
Applied Open Vacuum leaks
Closed Vacuum
maintained
AK100016