engine MITSUBISHI LANCER EVOLUTION VI 1999 Workshop Manual
[x] Cancel search | Manufacturer: MITSUBISHI, Model Year: 1999, Model line: LANCER EVOLUTION VI, Model: MITSUBISHI LANCER EVOLUTION VI 1999Pages: 558, PDF Size: 9.73 MB
Page 131 of 558
MPI – Troubleshooting
Vehicle
speedInitial accel-
erator pedal
depression
NormalHesitation
Sag
Time
(Figure 1)(Figure 2)
Normal
Initial accel-
erator pedal
depression
IdlingStumble
TimeVehicle
speed
13-19
PROBLEM SYMPTOMS TABLE (FOR YOUR INFORMATION)
ItemsSymptom
StartingWon’t startThe starter is used to crank the engine, but there is no combustion within the
cylinders, and the engine won’t start.
Fires up and diesThere is combustion within the cylinders, but then the engine soon stalls.
Hard startingEngine starts after cranking a while.
Idling
stability
HuntingEngine speed doesn’t remain constant; changes at idle.
stability
Rough idleUsually, a judgement can be based upon the movement of the tachometer
pointer, and the vibration transmitted to the steering wheel, shift lever, body, etc.
This is called rough idle.
Incorrect idle speedThe engine doesn’t idle at the usual correct speed.
Engine stall
(Die out)The engine stalls when the foot is taken from the accelerator pedal, regardless
of whether the vehicles is moving or not.
Engine stall
(Pass out)The engine stalls when the accelerator pedal is depressed or while it is being
used.
DrivingHesitation, Sag“Hesitation” is the delay in response of the vehicle speed (engine speed) that
occurs when the accelerator is depressed in order to accelerate from the speed
at which the vehicle is now traveling, or a temporary drop in vehicle speed
(engine speed) during such acceleration. Serious hesitation is called “sag”.
(Refer to Figure 1.)
Poor accelerationPoor acceleration is inability to obtain an acceleration corresponding to the
degree of throttle opening, even though acceleration is smooth, or the inability
to reach maximum speed.
StumbleEngine speed increase is delayed when the accelerator pedal is initially
depressed for acceleration. (Refer to Figure 2.)
ShockThe feeling of a comparatively large impact or vibration when the engine is
accelerated or decelerated.
SurgeThis is repeated surging ahead during constant speed travel or during variable
speed travel.
KnockingA sharp sound like a hammer striking the cylinder walls during driving and which
adversely affects driving.
StoppingRun on
(“Dieseling”)The condition in which the engine continues to run after the ignition switch is
turned to OFF. Also called “Dieseling”.
Page 132 of 558
MPI – Troubleshooting13-20
INSPECTION PROCEDURE FOR TROUBLE SYMPTOMS
INSPECTION PROCEDURE 1
Communication with MUT-II is impossible.
(Communication with all systems is impossible.)
Probable cause
The cause is probably a defect in the power supply system (including earth) for the
diagnosis line.Malfunction of the diagnosis connector
Malfunction of the harness wire
Measure at the diagnostic connector
B-22.
Voltage between 16 and earth
OK:System voltageNGCheck the following connectors:
Repair
OK
Check trouble symptom.NGCheck the harness wire between the
power supply and diagnostic connector,
and repair if necessary.OK
Measure at the diagnostic connector
B-22.
Continuity between 4 and earth
Continuity between 5 and earth
OK:ContinuityNGCheck the earth wire, and repair if nec-
essary.
OK
Replace the MUT-II.
INSPECTION PROCEDURE 2
MUT-II communication with engine-ECU is impossible.
Probable cause
One of the following causes may be suspected.
No power supply to engine-ECU.
Defective earth circuit of engine-ECU.
Defective engine-ECU.
Improper communication line between engine-ECU and MUT-IIMalfunction of engine-ECU power supply circuit
Malfunction of engine-ECU
Open circuit between immobilizer-ECU and diagnosis
connector
OK
Check the engine-ECU power supply and earth circuit.
(Refer to P.13-53, INSPECTION PROCEDURE 45.)
NG
Check the harness wire between engine-ECU and diagnosis con-
nector.NG
Repair
OK
Check trouble symptom.
Check the following connectors:
B-22, B-65, B-32, B-61NG
Repair
Page 133 of 558
MPI – Troubleshooting13-21
INSPECTION PROCEDURE 3
The engine warning lamp does not illuminate right after
the ignition switch is turned to the ON position.
Probable cause
For checking for burnt-out bulb, the engine-ECU causes the engine warning lamp
to illuminate for five seconds immediately after the ignition switch is turned to ON.
If the engine warning lamp does not illuminate immediately after the ignition switch
is turned to ON, one of the malfunctions listed at right has probably occurred.Burnt-out bulb of the engine warning lamp
Defective engine warning lamp circuit
Malfunction of the engine-ECU
MUT-II Data list
16 engine-ECU power supply voltage (Refer to P.13-57)NGCheck the engine-ECU power supply and earth circuit.
(Refer to P.13-53, INSPECTION PROCEDURE 45.)
OK
Measure at the engine-ECU connector B-60.
Disconnect the connector, and measure at the harness side.
Earth the terminal No.36. (Ignition switch: ON)
OK:The engine warning lamp illuminates.OKCheck the following
connector: B-60NG
Repair
OK
Check trouble symptom.
NG
Replace the engine-ECU.
NG
Check for burnt-out bulb.NG
Replace
OK
Measure at the combination meter connector B-08.
Disconnect the connector, and measure at the harness side.
Voltage between 42 and earth (Ignition switch: ON)
OK:System voltageNGCheck the engine warning lamp power supply circuit, and repair
if necessary.
OK
Check the following connectors:
B-08, B-65, B-60NG
Repair
OK
Check trouble symptom.NGCheck the harness wire between combination meter and engine-
ECU connector, and repair if necessary.
INSPECTION PROCEDURE 4
The engine warning lamp remains illuminating and never
goes out.
Probable cause
In cases such as the above, the cause is probably that the engine-ECU is detecting
a problem in a sensor or actuator, or that one of the malfunctions listed at right has
occurred.Short-circuit between the engine warning lamp and
engine-ECU
Malfunction of the engine-ECU
MUT-II Self-Diag code
Are diagnosis codes displayed?Ye sRefer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
No
Measure at the combination meter connector B-08.
Disconnect the connector, and measure at the harness side.
Disconnect the engine-ECU connector
Continuity between 53 and earth
OK:No continuityNGCheck the harness wire between combination meter and engine-
ECU connector, and repair if necessary.
OK
Replace the engine-ECU.
Page 134 of 558
MPI – Troubleshooting13-22
INSPECTION PROCEDURE 5
No initial combustion (starting impossible)
Probable cause
In cases such as the above, the cause is probably that a spark plug is defective,
or that the supply of fuel to the combustion chamber is defective.
In addition, foreign materials (water, kerosene, etc.) may be mixed with the fuel.Malfunction of the ignition system
Malfunction of the fuel pump system
Malfunction of the injectors
Malfunction of the engine-ECU
Foreign materials in fuel
Check system voltage when cranking.
OK:8 V or higherNGCheck the battery.
OK
MUT-II: Inspection of no initial combustion.
(Refer to P.13-47, INSPECTION PROCEDURE 37.)
OK
Can any sound be heard from the injectors when cranking (check
using a soundscope)?NGCheck the injector system. (Refer to P.13-15, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE 41.)
OK
Ignition system: Inspection of no initial combustion.
(Refer to P.13-47, INSPECTION PROCEDURE 38.)
OK
Check the following items.
Check the ignition coil, spark plugs, spark plug cables.
Check if the injectors are clogged.
Check if foreign materials (water, alcohol, etc.) got into fuel.
Check the compression pressure.
Page 135 of 558
MPI – Troubleshooting13-23
INSPECTION PROCEDURE 6
Initial combustion but no complete combustion
(starting impossible)
Probable cause
In such cases as the above, the cause is probably that the spark plugs are generating
sparks but the sparks are weak, or the initial mixture for starting is not appropriate.Malfunction of the ignition system
Malfunction of the injector system
Foreign materials in fuel
Poor compression
Malfunction of the engine-ECU
Check system voltage when cranking.
OK:8 V or higherNGCheck the battery.
OK
MUT-II: Check if uncompleted combustion occurs.
(Refer to P.13-48, INSPECTION PROCEDURE 39.)
OK
Can any sound be heard from the injectors when cranking (check
using a soundscope)?NGCheck the injector system, (Refer to P.13-15, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE 41.)
OK
Is starting good if the engine is cranked with the accelerator pedal
slightly depressed?Ye sCheck ISC servo for op-
eration sound. NGCheck the ISC servo sys-
tem. (Refer to P.13-44, IN-
SPECTION PROCE-
DURE 33.)
OK
Clean the throttle valve area.
Adjust the fixed SAS. (Refer to P.13-30.)*
No
Check the ignition timing when cranking.
OK:Approx. 5BTDCNGCheck that the crank angle sensor and the timing belt cover are
installed properly.
OK
Check the following items.
Check the ignition coil, spark plugs, spark plug cables.
Check the injectors for clogging and leakage.
Check the compression pressure.
Check fuel lines for clogging.
Check if foreign materials (water, alcohol, etc.) got into fuel.
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).
Page 137 of 558
MPI – Troubleshooting13-25
INSPECTION PROCEDURE 8
Unstable idling (Rough idling, hunting)
Probable cause
In cases as the above, the cause is probably that the ignition system, air/fuel mixture,
idle speed control (ISC) or compression pressure is defective.
Because the range of possible causes is broad, inspection is narrowed down to simple
items.Malfunction of the ignition system
Malfunction of air-fuel ratio control system
Malfunction of the ISC servo system
Poor compression
Drawing air into exhaust system
Secondary air backflow to the intake system
Were the battery terminals disconnected recently?Ye sAfter warming-up, let the engine run at idling for about 10 minutes.
No
MUT-II Self-Diag code
Are diagnosis codes displayed?Ye sRefer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
No
Does idling speed fluctuate excessively?Ye sCheck if hunting occurs.
(Refer to P.13-48, INSPECTION PROCEDURE 40.)
No
Check the ISC servo for operation sound.NGCheck the ISC servo system.
(Refer to P.13-44, INSPECTION PROCEDURE 33.)
OK
Check the injector for operation.NGCheck the injector system. (Refer to P.13-15, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE 41.)
OK
MUT-II: Check if idling speed is unstable.
(Refer to P.13-49, INSPECTION PROCEDURE 41.)
OK
Check the ignition timing.
(Refer to GROUP 11 – Engine Adjustment.)*NGCheck that the crank angle sensor and the timing belt cover are
installed properly.
OK
Check the following items.
Check the ignition coil, spark plugs, spark plug cables.
Check the secondary air supply system. (Ensure that there is no back flow of secondary air into the intake system.)
Check the compression pressure.
Check if foreign materials (water, alcohol, etc.) got into fuel.
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).
Page 138 of 558
MPI – Troubleshooting13-26
INSPECTION PROCEDURE 9
Idling speed is high. (Improper idling speed)
Probable cause
In such cases as the above, the cause is probably that the intake air volume during
idling is too great.Malfunction of the ISC servo system
Malfunction of the throttle body
OK
MUT-II Data list
26 Idle position switch (Refer to P.13-58.)NGCheck the idle position switch system.
(Refer to P.13-38, INSPECTION PROCEDURE 26.)
No
Check the ISC servo for operation sound.NGCheck the ISC servo system.
(Refer to P.13-44, INSPECTION PROCEDURE 33.)
OK
MUT-II Data list
21 Engine coolant temperature sensor (Refer to P.13-57.)NGCheck the engine coolant temperature sensor system.
(Refer to P.13-10, INSPECTION PROCEDURE FOR DIAGNOSIS
CODE 21.)
OK
MUT-II Data list
28 A/C switch (Refer to P.13-58.)NGCheck the A/C switch and A/C relay system.
(Refer to P.13-39, INSPECTION PROCEDURE 29.)
OK
Basic idle speed adjustment (Refer to P.13-30.)*
Check trouble symptom.NGClean the throttle valve area.
Adjust the fixed SAS. (Refer to P.13-30.)*
MUT-II Self-Diag code
Are diagnosis codes displayed?Ye sRefer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).
Page 139 of 558
MPI – Troubleshooting13-27
INSPECTION PROCEDURE 10
Idling speed is low. (Improper idling speed)
Probable cause
In cases such as the above, the cause is probably that the intake air volume during
idling is too small.Malfunction of the ISC servo system
Malfunction of the throttle body
MUT-II Self-Diag code
Are diagnosis codes displayed?Ye sRefer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
No
Check the ISC servo for operation sound.NGCheck the ISC servo system.
(Refer to P.13-44, INSPECTION PROCEDURE 33.)
OK
MUT-II Data list
26 Idle position switch (Refer to P.13-58.)NGCheck the idle position switch system.
(Refer to P.13-38, INSPECTION PROCEDURE 26.)
OK
MUT-II Data list
21 Engine coolant temperature sensor (Refer to P.13-57.)NGCheck the engine coolant temperature sensor system.
(Refer to P.13-10, INSPECTION PROCEDURE FOR DIAGNOSIS
CODE 21.)
OK
Basic idle speed adjustment (Refer to P.13-30.)*
Check trouble symptom.NGClean the throttle valve area.
Adjust the fixed SAS. (Refer to P.13-30.)*
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).
Page 140 of 558
MPI – Troubleshooting13-28
INSPECTION PROCEDURE 11
When the engine is cold, it stalls at idling. (Die out)
Probable cause
In such cases as the above, the cause is probably that the air/fuel mixture is inappropriate
when the engine is cold, or that the intake air volume is insufficient.Malfunction of the ISC servo system
Malfunction of the throttle body
Malfunction of the injector system
Malfunction of the ignition system
Were the battery terminals disconnected recently?Ye sAfter warming-up, let the engine run at idling for about 10 minutes.
No
MUT-II Self-Diag code
Are diagnosis codes displayed?Ye sRefer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
OK
Check the fuel pressure. (Refer to P.13-30.)*
OK
Check the ignition timing.
(Refer to GROUP 11 – Engine Adjustments.)*NGCheck that the crank angle sensor and the timing belt cover are
installed properly.
OK
Check the following items.
Check the ignition coil, spark plugs, spark plug cables.
Check the compression pressure.
Check the engine oil viscosity.
OK
MUT-II Data list
26 Idle position switch (Refer to P.13-58.)NGCheck the idle position switch system.
(Refer to P.13-38, INSPECTION PROCEDURE 26.)
OK
Check the injector for operation sound.NGCheck the injector system. (Refer to P.13-15, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE 41.)
Ye s
Check the ISC servo for operation sound.NGCheck the ISC servo system.
(Refer to P.13-44, INSPECTION PROCEDURE 33.)
No
Is engine-idling stable after the warming-up?NoCheck for unstable idling (Rough idling, hunting).
(Refer to P.13-25, INSPECTION PROCEDURE 8.)
No
Does the engine stall right after the accelerator pedal is released?Ye sClean the throttle valve
area.Adjust the fixed SAS.
(Refer to P.13-30.)*
OK
MUT-II Data list
21 Engine coolant temperature sensor (Refer to P.13-57.)NGCheck the engine coolant temperature sensor system.
(Refer to P.13-10, INSPECTION PROCEDURE FOR DIAGNOSIS
CODE 21.)
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).
Page 141 of 558
MPI – Troubleshooting13-29
INSPECTION PROCEDURE 12
When the engine is hot, it stalls at idling. (Die out)
Probable cause
In such cases as the above, the cause is probably that ignition system, air/fuel mixture,
idle speed control (ISC) or compression pressure is defective.
In addition, if the engine suddenly stalls, the cause may also be a defective connector
contact.Malfunction of the ignition system
Malfunction of air-fuel ratio control system
Malfunction of the ISC servo system
Drawing air into intake system
Improper connector contact
Backflow of secondary air to the intake system
Were the battery terminals disconnected recently?Ye sAfter warming-up, let the engine run at idling for about 10 minutes.
No
MUT-II Diagnosis code
Are diagnosis codes displayed?Ye sRefer to P.13-8, INSPECTION CHART FOR DIAGNOSIS CODES.
No
Check the ISC servo for operation sound.NGCheck the ISC servo system.
(Refer to P.13-44, INSPECTION PROCEDURE 33.)
OK
Check the injector for operation sound.NGCheck the injector system. (Refer to P.13-15, INSPECTION PRO-
CEDURE FOR DIAGNOSIS CODE 41.)
OK
Does the engine stall right after the accelerator pedal is released?Ye sClean the throttle valve
area.Adjust the fixed SAS.
(Refer to P.13-30.)*
No
Does the engine stall easily again?NoWhile carrying out an intermittent malfunction simulation test (Refer
to GROUP 00 – Points to Note for Intermittent Malfunctions.), check
for sudden changes in the signals shown below.
Crank angle sensor signal
Injector drive signal
Fuel pump drive signal
Air flow sensor signalSecondary ignition signal
Engine-ECU power supply
voltage
Ye s
MUT-II: Engine stalling inspection when the engine is warm and
idling. (Refer to P.13-50, INSPECTION PROCEDURE 42.)
OK
Check the ignition timing.
(Refer to GROUP 11 – ENGINE ADJUSTMENTS.)*NGCheck that the crank angle sensor and the timing belt cover are
installed properly.
OK
Check the following items.
Check the ignition coil, spark plugs, spark plug cables.
Check the secondary air supply system. (Ensure that there is no backflow of secondary air into the intake system.)
Check if the injectors are clogged.
Check the compression pressure.
Check if foreign materials (water, alcohol, etc.) got into fuel.
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).