check engine MITSUBISHI TRITON 1997 Repair Manual

MPI ± Troubleshooting13A-59
Item
No.Reference
page Inspection
procedure
No. Normal condition Inspection contents Inspection
item
22Crank angle
sensor
Engine: Cranking

Tachometer:
ConnectedCompare the engine
speed readings on
the tachometer and
the MUT-II.AccordCode No.
2213A-15

Engine: Idling

Idle position
switch: ONWhen engine
coolant temperature
is ±20C1,275 ± 1,475 r/min
When engine
coolant temperature
is 0C1,225 ± 1,425 r/min
When engine
coolant temperature
is 20C1,100 ± 1,300 r/min
When engine
coolant temperature
is 40C950 ± 1,150 r/min
When engine
coolant temperature
is 80C650 ± 850 r/min
25Barometric
p
ressure
Ignition switch: ONAt altitude of 0 m101 kPaCode No.
25
13A-18
ressure
sensorAt altitude of 600 m95 kPa
25
At altitude of 1,200 m88 kPa
At altitude of 1,800 m81 kPa
26Idle position
switchIgnition switch: ON
Check by operating
acceleratorpedal
Throttle valve:
Set to idle positionONProcedure
No. 2513A-40
accelerator pedal
repeatedlyThrottle valve:
Slightly openOFF*2
27Power
steering fluid
p
ressure
Engine: IdlingSteering wheel
stationaryOFFProcedure
No. 2813A-43
pressure
switchSteering wheel
turningON

MPI ± Troubleshooting13A-60
Item
No.Reference
page Inspection
procedure
No. Normal condition Inspection contents Inspection
item
28A/C switchEngine: Idling
(when A/C switch isA/C switch: OFFOFFProcedure
No. 2913A-43
(
ON, A/C compressor
should be operating.)A/C switch: ONON
29Inhibitor
switch
Ignition switch: ONP or NP or NProcedure
No 27
13A-42
switch
D, 2, L or RD, 2, L or R
No. 27
41Injectors *3Engine: CrankingWhen engine cool-
ant temperature is
0C51 ± 76 ms
<4G63>
60 ± 90 ms
<4G64>±±
When engine
coolant temperature
is 20C26 ± 38 ms
<4G63>
30 ± 45 ms
<4G64>
When engine
coolant temperature
is 80C5.7 ± 8.5 ms
<4G63>
6.7 ± 10.1 ms
<4G64>
Injectors*4
Engine coolant
temperature:
80 ± 95C

Lamps and all
accessories: OFF
Engine is idling1.9 ± 3.1 ms
<4G63>
2.2 ± 3.4 ms
<4G64>
accessories: OFF

Transmission:
Neutral (A/T :
P range)2,500 r/min1.8 ± 3.0 ms
<4G63>
1.9 ± 3.1 ms
<4G64>
When engine is
suddenly racedIncreases
44Ignition coils
and power
Engine: After
having warmed upEngine is idling2±18BTDC±±
transistors
g

Timing lamp is set.
(The timing lamp
is set in order to
check actual
ignition timing.)2,500 r/min23 ± 43 BTDC
<4G63>
27 ± 47 BTDC
<4G64>

MPI ± Troubleshooting13A-62
ACTUATOR TEST REFERENCE TABLE13100900210
Item
No.Inspection
itemDrive contentsInspection contentsNormal conditionInspection
procedure
No.Reference
page
01InjectorsCut fuel to No.1,
No.3 injectorEngine:
After having warmed up/En-
gine is idling
(Cut the fuel supply to each
Idling condition
becomes different
(becomes unsta-
ble)
Code No.
4113A-19
02Cut fuel to No.2,
No.4 injector(Cut the fuel supply to each
injector in turn and check
cylinders which don't affect
idling.)
ble).
07Fuel pumpFuel pump
operates and
fuel is recircu-
lated.
Engine:
Cranking

Fuel
pump:
Forced
driving
Inspect
accord-
Pinch the
return hose
with fingers
to feel the
pulse of the
fuel being
recirculated.Pulse is felt.Procedure
No. 2413A-40
accord-
ing to
both the
above
condi-
tions.
Listen near
the fuel tank
for the
sound of fuel
pump
operation.Sound of operation
is heard.
08Purge
control
solenoid
valveSolenoid valve
turns from OFF
to ON.Ignition switch: ONSound of operation
can be heard when
solenoid valve is
driven.Procedure
No. 3213A-45
10EGR
control
solenoid
valveSolenoid valve
turns from OFF
to ON.Ignition switch: ONSound of operation
can be heard when
solenoid valve is
driven.Procedure
No. 3313A-46

MPI ± Troubleshooting13A-65
Terminal No.Normal condition Check condition (Engine condition) Check item
35Oxygen sensor heaterEngine: Idling after warming up0±3V
Engine r/min: 5,000r/min.System voltage
36Engine warning lampIgnition switch: OFF
ON0 ± 3V
9 ± 13V
(After several seconds have
elapsed)
37Power steering fluid
pressure switchEngine: Idling after
warming upWhen steering
wheel is stationarySystem voltage
When steering
wheel is turned0±3V
38Control relay
(Power supply)
Ignition switch: OFFSystem voltage
(Power su ly)
Ignition switch: ON0±3V
45A/C switchEngine: Idle speedTurn the A/C
switch OFF0±3V
Turn the A/C
switch ON (A/C
compressor is
operating)System voltage
51Ignition switch ± STEngine: Cranking8V or more
52Intake air temperature
sensorIgnition switch:
ONWhen intake air
temperature is
0
C3.2 ± 3.8V
When intake air
temperature is
20
C2.3 ± 2.9V
When intake air
temperature is
40
C1.5 ± 2.1V
When intake air
temperature is
80
C0.4 ± 1.0V
56Oxygen sensorEngine: Running at 2,500 r/min after
warmed up (Check using a digital type
voltmeter)0
0.8V
(Changes repeatedly)
60Backup power supplyIgnition switch: OFFSystem voltage
61Sensor impressed
voltageIgnition switch: ON4.5 ± 5.5V
62Ignition switch ± IGIgnition switch: ONSystem voltage

MPI ± TroubleshootingMPI ± Troubleshooting13A-66
Terminal No.Normal condition Check condition (Engine condition) Check item
63Engine coolant
temperature sensorIgnition switch:
ONWhen engine
coolant tempera-
ture is 0C3.2 ± 3.8V
When engine
coolant tempera-
ture is 20C2.3 ± 2.9V
When engine
coolant tempera-
ture is 40C1.3 ± 1.9V
When engine
coolant tempera-
ture is 80C0.3 ± 0.9V
64Throttle position
sensorIgnition switch:
ONSet throttle valve
to idle position0.3 ± 1.0V
Fully open throttle
valve4.5 ± 5.5V
65Barometric pressure
sensorIgnition switch:
ONWhen altitude is
0m3.7 ± 4.3V
When altitude is
1,200m3.2 ± 3.8V
66Vehicle speed sensor
Ignition switch: ON

Move the vehicle slowly forward0
5V
(Changes repeatedly)
67Idle position switchIgnition switch:
ONSet throttle valve
to idle position0±1V
Slightly open
throttle valve4V or more
68Top dead centre sensorEngine: Cranking0.4 ± 3.0V
Engine: Idle speed0.5 ± 2.0V
69Crank angle sensorEngine: Cranking0.4 ± 4.0V
Engine: Idle speed1.5 ± 2.5V
70Air flow sensorEngine: Idle speed2.2 ± 3.2V
Engine r/min: 2,500r/min
71Inhibitor switch Ignition switch:
ONSet selector lever
to P or N0±3V
Set selector lever
to Other than P or
N8 ± 14V

MPI ± Troubleshooting13A-68
Terminal No. Normal condition (Check condition)Inspection item
4±12Stepper motor coil (A1)28 ± 33 W (At 20
C)
17 ± 12Stepper motor coil (A2)
5±12Stepper motor coil (B1)
18 ± 12Stepper motor coil (B2)
6±12EGR control solenoid valve36 ± 44 W (At 20
C)
9±12Purge control solenoid valve36 ± 44 W (At 20
C)
13 ± Body earthEngine-ECU earthContinuity (0W)
26 ±Body earthEngine-ECU earth
35 ± 12Oxygen sensor heaterApprox. 12 W (At 20
C)
52 ± 72Intake air temperature sensor5.3 ± 6.7 kW (When intake air temperature is 0
C)
2.3 ± 3.0 kW (When intake air temperature is 20
C)
1.0 ± 1.5 kW (When intake air temperature is 40
C)
0.30 ± 0.42 kW (When intake air temperature is 80
C)
63 ± 72Engine coolant temperature sensor5.1 ± 6.5 kW (When coolant temperature is 0
C)
2.1 ± 2.7 kW (When coolant temperature is 20
C)
0.9 ± 1.3 kW (When coolant temperature is 40
C)
0.26 ± 0.36 kW (When coolant temperature is 80
C)
67 ± 72Idle position switchContinuity (when throttle valve is at idle position)
No continuity (when throttle valve is slightly open)
71 ±Body earthInhibitor switch Continuity (when select lever is at P or N)
No continuity (when select lever is at D, 2, L or R)

MPI ± On-vehicle Service13A-83
14. Stop the engine and check change of fuel pressure gauge
reading. Normal if the reading does not drop within 2
minutes. If it does, observe the rate of drop and
troubleshoot and repair according to the table below.
SymptomProbable causeRemedy
Fuel pressure drops gradually after
engine is stopped
Leaky injectorReplace injector
engine is sto ed
Leaky fuel regulator valve seatReplace fuel pressure regulator
Fuel pressure drops sharply
immediately after engine is stoppedCheck valve in fuel pump is held openReplace fuel pump
15. Release residual pressure from the fuel pipe line. (Refer
to P.13A-84.)
16. Remove the fuel pressure gauge and special tool from
the delivery pipe.
Caution
Cover the hose connection with rags to prevent splash
of fuel that could be caused by some residual pressure
in the fuel pipe line.
17. Replace the O-ring at the end of the fuel high pressure
hose with a new one. Furthermore, apply engine oil to
the new O-ring before replacement.
18. Fit the fuel high pressure hose over the delivery pipe
and tighten the bolt to specified torque.
Tightening torque: 5 Nm
19. Check for fuel leaks.
(1) Apply the battery voltage to the fuel pump drive
terminal to drive the fuel pump.
(2) Under fuel pressure, check the fuel line for leaks.

MPI ± Injector13A-93
REMOVAL SERVICE POINT
A
DELIVERY PIPE/INJECTOR REMOVAL
Remove the delivery pipe (with the injectors attached to it).
Caution
Care must be taken, when removing the delivery pipe,
not to drop the injector.
INSTALLATION SERVICE POINT

AINJECTOR/FUEL PRESSURE REGULATOR/
HIGH-PRESSURE FUEL HOSE INSTALLATION
(1) Apply a drop of new engine oil to the O-ring.
Caution
Be sure not to let engine oil in the delivery pipe.
(2) While turning the injector, high-pressure fuel hose and
fuel pressure regulator to the right and left, install the
delivery pipe, while being careful not to damage the O-ring.
After installing, check that the hose turns smoothly.
(3) If it does not turn smoothly, the O-ring may be trapped,
remove the fuel pressure regulator and then re-insert
it into the delivery pipe and check once again.
(4) Tighten the high-pressure fuel hose and fuel pressure
regulator to the specified torque.
Tightening torque:
9 Nm (Fuel pressure regulator)
5 Nm (High-pressure fuel hose)

ENGINE COOLING ± Cooling Fan14-6
INSPECTION14100220023
COOLING FAN CHECK

Check blades for damage and cracks.

Check for cracks and damage around bolt holes in fan
hub.

If any portion of fan is damaged or cracked, replace cooling
fan.
FAN CLUTCH CHECK

Check to ensure that fluid in fan clutch is not leaking
at case joint and seals. If fluid quantity decreases due
to leakage, fan speed will decrease and engine
overheating might result.

When a fan attached to an engine is turned by hand,
it should give a sense of some resistance. If fan turns
lightly, it is faulty.

Check bimetal strip for damage.

ENGINE ELECTRICAL ± Charging System16-6
This test determines whether the alternator output
current is normal.
(1) Before the test, always be sure to check the
following.

Alternator installation

Battery (Refer to GROUP 54 ± Battery.)
NOTE
The battery should be slightly discharged.
The load needed by a fully-charged battery
is insufficient for an accurate test.

Alternator drive belt tension (Refer to
GROUP 11 ± On-vehicle Service.)

Fusible link

Abnormal noise from the alternator while
the engine is running.
(2) Turn the ignition switch off.
(3) Disconnect the negative battery cable.
(4) Disconnect the alternator output wire from the
alternator ªBº terminal. Connect a DC test
ammeter with a range of 0 ± 100 A in series
between the ªBº terminal and the disconnected
output wire. (Connect the (+) lead of the
ammeter to the ªBº terminal. Connect the (±)
lead of the ammeter to the disconnected output
wire.)
Caution
Never use clips but tighten bolts and nuts
to connect the line. Otherwise loose
connections (e.g. using clips) will lead to
a serious accident because of high current.
NOTE
An inductive-type ammeter which enables
measurements to be taken without
disconnecting the alternator output wire should
be recommended.
(5) Connect a voltmeter with a range of 0 ± 20 V
between the alternator ªBº terminal and the
earth. (Connect the (+) lead of the voltmeter
to the ªBº terminal, and then connect the (±)
lead of the voltmeter to the earth.)
(6) Connect the negative battery cable.
(7) Connect a tachometer. (Refer to GROUP 11
± On-vehicle Service.)
(8) Leave the hood open.
(9) Check that the reading on the voltmeter is equal
to the battery voltage.
NOTE
If the voltage is 0 V, the cause is probably
an open circuit in the wire or fusible link between
the alternator ªBº terminal and the battery (+)
terminal.(10)Turn the light switch on to turn on headlamps
and then start the engine.
(11) Immediately after setting the headlamps to high
beam and turning the heater blower switch to
the high revolution position, increase the engine
speed to 2,500 r/min and read the maximum
current output value displayed on the ammeter.
Limit: 70% of normal current output
NOTE

For the nominal current output, refer to the
Alternator Specifications.

Because the current from the battery will
soon drop after the engine is started, the
above step should be carried out as quickly
as possible in order to obtain the maximum
current output value.

The current output value will depend on
the electrical load and the temperature of
the alternator body.

If the electrical load is small while testing,
the specified level of current may not be
output even though the alternator is normal.
In such cases, increase the electrical load
by leaving the headlamps turned on for
some time to discharge the battery or by
using the lighting system in another vehicle,
and then test again.

The specified level of current also may not
be output if the temperature of the alternator
body or the ambient temperature is too
high. In such cases, cool the alternator and
then test again.
(12)The reading on the ammeter should be above
the limit value. If the reading is below the limit
value and the alternator output wire is normal,
remove the alternator from the engine and
check the alternator.
(13)Run the engine at idle after the test.
(14)Turn the ignition switch off.
(15)Remove the tachometer.
(16)Disconnect the negative battery cable.
(17)Disconnect the ammeter and voltmeter.
(18)Connect the alternator output wire to the
alternator ªBº terminal.
(19)Connect the negative battery cable.