1989 MITSUBISHI GALANT lights

FUEL SYSTEM - On-Vehicule Inspection of MFI Components13-65
(1) Improper adjustment of the basic idling speed.
(2) Deposits adhering to the ttirottle valve.
(3) Air being taken into the intake manifold due to a gasket leak, etc.
OPERATION
ISC motor position sensor is a variable resistor type,
and is integrated in the
ISC motor system. The slid-
ing pin of
ISC motor position sensor is in contact
with the end of the plunger. Therefore, as the plun- ger moves, the internal resistance of
ISC motor pos-
ition sensor varies. This leads to the variation of the (4) Improper seating of the EGR valve seat.
(5) lmcomplete combustion within a cylinder. (Mal-
function of spark plugs, ignition coil, injectors,
compression pressure, etc.)
the plunger position of the
ISC motor system, and
sends the signal to ECM. ECM processes the
ISC
motor position sensor signal, idle signal, coolant
temperature signal, load signal (A/T &
A/C) and ve-
hicle speed signal to control the opening angle of
the throttle valve and revolution speed during
en-
output voltage. ISC motor position sensor detects gine idling.
TROUBLESHOOTING HINTS
Since idling is not controlled when ISC motor posi-
tion sensor is troubled, idling may not be evenly
maintained.
INSPECTION
Using Scan tool
FunctionItem No. Data display Inspection conditions Load conditions
Standard value
Data reading 15 Sensor detec-
. Engine coolant tempera-
Air conditioning 500- 1,300 mV
tion voltage
ture: 85-95’C (185-203°F)
switch: OFF
. Lights, cooling fan, electrical accessories: OFF Air conditioning 800-
1,800 mV. Transaxle: neutral (A/T
mod-
switch: ON
els: “P”
range)
1 Closed throttle position Air conditioning900- 1,900 mVswitch: ON (The compressorswitch: ON
clutch must be operating Select lever:
when the air conditioning shift to “D”
switch is ON.)
range.* Engine: running at idle
NOTEThe idle speed control motor position sensor output voltage may be about\
500 mV higher than indicated above when
the vehicle is new [driven approximately 500 km (300 miles) or less].
CautionBefore shifting the select lever to the “D” range, apply the brake\
s to prevent the vehicle from moving forward.
HARNESS INSPECTION
Measure the power supply voltage of
the idle speed control motor position
ei;;;it;;sco$ected
__...._ -.-
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FUEL SYSTEM -On-Vehicule
Inspection of MFI Components13-91
INSPECTION
Using Scan tool
FunctionItem No. Data display
Data reading 41
III~~~ion
Inspection conditions Engine coolant temperature Standard value
Engine cranking At
0°C (3~2°F)“~Approx. 21 ms
At
20°C (68°F)Approx. 43 ms
At
80°C (176°F)Approx. 10 ms
FunctionItem No.
Data reading 41
L
Data display
Ac&a$ion
Inspection conditions
. Engine coolant tempera- ture:
85-95°C (185-205°F)* Lights, cooling fan, electric-al accessories: OFF
. Transaxle: neutral
(A/T models: “P” range) Engine condition
Standard value
I
750 rpm (Idling)2.5-4.0 ms
I
NOTE*I: The injector activation time indicates the time under the following con\
ditions: a power source voltage of 11V and a
cranking rpm of 250 rpm or less.
**: Simultaneous injection at four cylinders when engine coolant temperatur\
e is 0°C (32°F).*3: The injector activation time may be about 10% longer than indicated abo\
ve when the vehicle is new [driven approximately 500 km (300 miles) or less].
FunctionItem No.
Actuator test
01
02
03
04
Description
No.
1 injector is shut off.
No. 2 injector is shut off.
No. 3 injector is shut off.
No. 4 injector is shut off. Inspection conditions
Normal indication
Engine: idling after warm The idling condition
changes more.
r”sput off the injectors in(Either becomes more un-sequence during after stable, or engine stalls.)
engine warm-up, check
the idling condition.)
-
I i-. --.-~-db$- A: Injector~__
Normal waveformdrrve time
HARNESS INSPECTION
1
P
Using Oscilloscope
(1) Run the engine at idle speed.
(2) Connect the probe to the oscilloscope pick-up point as
shown in the circuit diagram, and check the waveform at
the drive side of each injector.
Measure the power supply voltage of
the injector.
. Connector: Disconnected. Ignition switch: ON
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I
4
i1
k ji,v,11
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YIY’.

FUEL SYSTEM - I?~FS~~ZFZLnt Procedures13-133
FUEL TANK AND FUEL LINEMIBEAAB
Symptom
Probable cause Remedy
Engine malfunctions
due to insufficient
fuel supply Bent or kinked fuel pipe or hose
Clogged fuel pipe or hose
Clogged fuel filter or in-tank fuel filter
Water in fuel filter Repair or replace
Clean or replace
Replace
Replace the fuel filter or clean the
fuel tank and fuel line
Dirty or rusted fuel tank interior
Clean or replace
Malfunctioning fuel pump
(Clogged filter in the pump)Replace
Evaporative emission
control system
malfunctions
[When fuel tank filler
tube cap is removed,
pressure releasingnoise is heard) Mispiping of vapor line
Disconnected vapor line piping joint
Folded, bent, cracked or clogged vapor line
Faulty fuel tank filler tube cap
Malfunctioning fuel tank pressure control valve Correct
Correct
Replace
Replace
Replace
SERVICE ADJUSTMENT
PROCEDURES
CURB IDLE SPEED INSPECTIONhll3MAE
(1) The vehicle should be prepared as follows before th
e
inspection.
lEngine coolant temperature: 85-95°C (185-203°F)
l Lights, electric cooling fan and accessories: OFF
l Transaxle: Neutral (P for vehicles with an automatic
transaxle)
(2) Connect a tachometer.
NOTE
Refer to
P.13-134 for information concerning connection Of
a tachometer.
(3) Set a timing light in position.
(4) Ground the terminal for adjustment of ignition timing.
(5) Start the engine and let it idle.
(6) Check whether or not the ignition timing is the standard
value; if not, adjust.
Standard value:
5”BTDC f 2”
(7) Stop grounding the terminal for adjustment of ignition timing.
(8) Let the engine idle for two minutes.
(9) Check the idling rpm.
Curb idle speed: 700
31100 rpm
NOTE
The idling rpm is automatically regulated by the idle aircontrol system.
(lO)lf not within the standard value range, refer to the CHECK
CHART CLASSIFIED BY PROBLEM SYMPTOMS and check
the
MFI component,
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13-134FUEL SYSTEM (SOHC-16 VALVE> -Service Adjustment Procedures
BASIC IDLE SPEED ADJUSTMENTMlIFHBX
NOTE
1. The standard idling speed has been adjusted, by the en-
gine speed adjusting screw, by the manufacturer, and
there should usually be no need for readjustment.
2. Use the following procedure to adjust when the idling speed drops due to an incorrect adjustment, high idling
speed, or when a load such as the air conditioning is ap-
plied on the engine.
3. The adjustment, if made, should be made after first con- firming that the spark plugs, the injectors, the idle air con-
trol motor, the compression pressure, etc. are all normal.
(I ) The vehicle should be prepared as follows before the inspec- tion and adjustment.
l Engine coolant temperature:
85-95°C (185-203°F)
l Lights, cooling fan and accessories: OFF
l Transaxle: neutral (A/T for
P range)
l Steering wheel: neutral position
(2) Connect the scan tool to the data link connector (white).
NOTE
When the scan tool is connected, the diagnostic test mode control terminal should be grounded.
(3) If the scan tool is not used, follow the steps below.
@I Insert a paper clip into the l-pin connector (blue) shown in the figure at the left.
0 Connect a primary-voltage-detection type of tacho-meter to the paper clip.
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On-Vehicle Inspection of MFI
13450FUEL SYSTEM VALVE> - Components
VOLUME AIR FLOW SENSOR
Intake air amountWsec)16245
1
@ Componentsideconnectof
Multiport
fuel
injection relay
/ohme air flow sensor/\2/\-
@Harness side
Isv xI 6FU1952
OPERATION TROUBLESHOOTING HINTSRefer to
P.13-49.
INSPECTION
Using Scan Tool
Item No.
12
Data displayInspection conditions Engine condition
Standard value
Sensor de- . Engine coolant Idle speed
18-44 Hz
tection airtemperature: 85-95°C
volume (fre- (185-205°F)
quency)
. Lights, cooling fan, elec-
2,000 rpm64-l 04 Hz tricaI
accessories: OFF
Transaxle: neutral
(PJTmodels: “P” range)RacingFrequency in-
creases as racing rpm increases.
NOTE
The volume air flow sensor output frequency may be about 10% higher than\
indicated above when the vehicle is new[driven approximately 500 km (300 miles) or less].
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FUEL SYSTEM - :::,:k:t?=tiion Of MF’13-163
INSPECTION
Using Scan Tool
Function
( Item No.
Data reading
/ 5
5
l-
+
L
Data display
IAC valve
position step
TCheck condition
l Engine coolant tem- perature: 85 to
95°C
(185 to 203’F)l Lights, electric cool- ing fan, accesso-
ries: OFF
l Transaxle: Neutral
(P range for A/T)
l Closed throttle posi-
tion switch: ON
l Engine: At idle
(Compressor clutch
to be operating in case air conditioning
switch is ON) Load state
Air conditioning switch:
OFF
Air conditioning switch:
Turn from OFF to ON l Air conditioning switch: OFF
l Selector lever: Shift to
D range
,,,,,,,,,I
Increase from 3-40 I
step
NfOTE
In a new vehicle [driven approximately 500 km (300 miles) or less], th\
e IAC valve position sometimes exceeds the
standard value by approximately 20 steps.
Caution
When shifting the selector lever to the
D range, apply brake to prevent the vehicle from moving forward.
HARNESS INSPECTION
IIL\-11 r@Harm ” ’ -conna
tA Engine control
-tmodule harnessside rnnnnctor
Check for open circuit, or short-circuit
to ground, between engine control module and
IAC valve position sensor.
l Engine control module connec- tor: Disconnected
l
IAC valve position sensor connec-
tor. Disconnected
21
@Harness sideconnector
0,OK-& 121
i Repair the
--L
harness
(@lcl- El)
/ ml-~) (@pJ
- @I)
Check for continuity of the ground
circuit.
l
IAC valve position sensor connec-
tor: Disconnected

13-182FUEL SYSTEM - ~~~;~~~t~pection Of MF’
INSPECTION
Using Scan Tool
Function1 Item
No. ’Data display 1Check conditionI Coolant temperature Standard value
IData reading / 41Drive trme
*’ 1Engine: Cranking0°C (32°F) *2Approx. 20 ms
j: 20°C (68°F)Approx. 40 ms 80°C
(176°F)/ Approx. 9.8 ms
Data reading
NOTE Item
No.
41 i
Data display 1
Check condition
IEngine state 1Standard value
Drive time
*3l Engine coolant temperature: 85 to
95°C (185 to 203°F)
l Lights, electric cooling fan, accesso-ries: OFF
l Transaxle: Neutral
(P range for AIT) Idle
speed
1 2.2-3.4 ms
*‘:The injector drive time refers to when the supply voltage is 11 V and the cranking speed is less than 250 rpm.
*2:When engine coolant temperature is lower than 0°C (32°F). injection is made by four cylinders simultaneously.
*3:When the vehicle is new [within initial operation of about 500 km (300 miles)], the injector drive time may be about
10% longer
Function Item No
.
Drive content Check condition Normal state
Actuator test
01No. 1 injector shut off Engine: Idling afterI Idle state to change further
0
2
No. 2 injector shut off
- warm-up
(becoming less stable or
(Shut off the injectors in stalling)
03li No. 3 injector shut off sequence during after-engine warm-up, check1
I04No. 4 injector shut off
the idling condition)
-k
Imp
4 AL A: Inje,t,r--m--m-Normal waveformdrive time03*0209
(1) Run the engine at idle speed.
(2) Connect the probe to the oscilloscope pick-up point as
shown in the circuit diagram, and check the waveform at
the drive side of each injector.
1
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Using Oscilloscope

FUEL SYSTEM - Service Adjustment Procedures13-245
cl989 models> -a’i\.-upI t
SERVICE ADJUSTMENT PROCEDURES
CURB IDLE SPEED INSPECTION
MlSFHAB
(1) The vehicle should be prepared as follows before the inspection.
l Engine coolant temperature:
85-95°C (185-205°F)
l Lights, electric cooling fan and accessories: OFF
l Transaxle: Neutral
(P for vehicles with an automatic
transaxle)
(2) Connect a tachometer.
NOTE
1. Refer to P.13-246 for information concerning connec-
tion of a tachometer.
2. For tachometer, one-half of the actual engine rpm is
indicated, so the actual engine rpm in two times the
indicated value shown by the tachometer. models>
(3) Set a timing light in position.
(4) Ground the terminal for adjustment of ignition timing.
(5) Start the engine and let it idle.
(6) Check whether or not the ignition timing
is the standard
value; if not, adjust.
Standard value:
5”BTDC f 2”
(7) Stop grounding the terminal for adjustment of ignition timing.
(8) Let the engine idle for two minutes.
(9) Check the idling rpm.
Curb idle speed:
75Ok 100 rpm
800+ 100 rpm
NOTE
The idling rpm is automatically regulated by the idle airsystem.
(10)lf not within the standard value range, refer to the CHECK
CHART CLASSIFIED BY PROBLEM SYMPTOMS and
check the
MFI component.
BASIC IDLE SPEED ADJUSTMENT
Ml3FHBl
NOTE
1. The standard idling speed has been adjusted, by the en- gine speed adjusting screw (RPM adjusting screw), by the
manufacturer, and there should usually be no need for
readjustment.
2. Use the following procedure to adjust when the idling speed drops due to an incorrect adjustment, high idling
speed, or when a load such as the air conditioning is ap-
plied on the engine.
3. The adjustment, if made, should be made after first con- firming that the spark plugs, the injectors, the idle air con-trol motor, the compression pressure, etc. are all
normal.~~-
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