display MITSUBISHI GALANT 1989 Service Owner's Guide

FUEL SYSTEM -On-Vehicle inspection of MFI Components13-267
INSPECTION
Using Scan tool
Function Item No.
Data display
Data reading
25Sensor detec-tion pressure
HARNESS INSPECTION
Check conditions1 Altitude1 Standard value
lanltion switch: ON1 At 0 m (0 ft.)LrnmmHq
At 600 m(1,969 ft.)710 mmHg
At 1,200 m660 mmHg(3,937 ft.)
At I:800
m610 mmHg
(5,906 ft.)
. Connector:Disconnected
Measure the power supply voltage Ofthe barometric pressure sensor.
connector
TSB Revision
-Engine controlmodule harness
side connector
6%
-

Check for an open-circuit, or a shqrt-circuit to ground, between the enginecontrol module and the barometricpressure sensor.
. Volume air flow sensor connec-tor: Disconnected@--/LA
- Engine control module connec-tor: Disconnected

1 V-L “IVILI.,. ““I ,“Ivn-ven,c,e lnsprcrlorl 91
l”lb-l b”mp”nerlrrI” L””
INSPECTION
Using Scan tool
FunctionItem No.Data display Check conditionsCoolant temperatureStandard value
Data reading
2 1Sensor de-Ignition switch: ONAt -20°C
(-4°F)- 20°CtectionOr, engine running
temperatureAt 0°C (32°F)0°C
At 20°C (68°F)20°C
At 40°C (104°F)40°C
At 80°C (176°F)80°C
HARNESS INSPECTION
@ Harnesssideconnector
OlL0463
connector
OlL0461
Check for continuity of the groundcircuit.
. Connector: Disconnected
Measure the power supply voltage.
. Connector: Disconnected. Ignition switch: ON
IVoltage (V)
4.5-4.9
SENSOR INSPECTION (1) Remove engine coolant temperature sensor from the
intake manifold.
(2) With temperature sensing portion of engine coolant
temperature sensor immersed in hot water check resist-
ance.
Temperature “C V’F)Resistance (kQ)
‘0(32)5.9
20(68)2.5
40
(104)1.1
80(176)0.3
(3) If the resistance deviates from the standard value greatly replace the sensor.
TSB Revision

FUEL SYSTEM - On-Vehicle Inspection of MFI Components13-271
TROUBLESHOOTING HINTS
Hint 1:
The signals of the throttle-position sensor are more
important for control of the automatic transaxle than
for control of the engine; shifting “impact shocks”
are produced if there is a malfunction of the
throttle-position sensor.
INSPECTION
Using Scan tool Hint 2:
If the voltage of the throttle-position sensor deviates
from the standard value, check once again after making the throttle-position sensor adjustment.
in
addition, if there are any indications that the fixedSAS has been moved, adjust the fixed SAS.
Function
Data readingItem No.Data display
14Sensor de-tection vol-
tage
HARNESS INSPECTION
connector
Harness side
connector
Inspection conditionsThrottle valve Standard value
Ignition switch: ON/ To idle position1 450-550
mV
Gradually opening Becomes higher
proportional to
valve opening.
To fully open 4,500-5,500

mV
Measure the power supply voltage of
the TPS.
. Connector: Disconnected
. Ignition switch: ON
Check for continuity of the ground
circuit of the TPS.
. Connector: Disconnected
Repair theharness.
+ K25xz.l-~~IZI)
LZheck for an open-circuit, or a shqrt-Yrcuit to ground, between the er-.--control module and the throttle ~USI-tion sensor.
. Throttle position sensor connec-tnr: Disconnected I
-
- Engine. control module connec-tor: DisconnectedRepair theharness.
u23Bl-m)
TSB Revision

FUEL SYSTEM - On-Vehicle Inspection of MFI Components13-275
INSPECTION
Using Scan tool
Function
Item No.
Data reading 26
Data displayInspection conditions Throttle valveNormal indication
Switch statusIgnition switch: ONTo idle positionON(Check after pumpingaccelerator several times.)
Slightly openedOFF
HARNESS INSPECTION
71
-
Harness side
Measure the power supply voltage of
the closed throttle position switch.
-. Connector: Disconnected
. Ignition switch: ON
1Voltage (VI
4 or more
ASTOP
Repair theharness.
~@a-Q)
ISENSOR INSPECTION
I(1) Disconnect the throttle position senso_r connector
(2) Check the continuity between terminal QI and body ground.
TSB Revision
Accelerator pedal Continuity
DepressedNon-conductive (m S2)
ReleasedConductive (0 52)
(3) If out of specification, replace the throttle position sensor
assembly.

13-286FUEL SYSTEM - On-Vehicle Inspection of MFI Components
INSPECTION Using Scan tool
Air conditioning switch
Function Item No.
Data reading 28
Data displayCheck conditionsAir conditioning switchNormal
display
Switch status
. Engine idlingOFF OFF
(The air conditioning
compressor should beONONactivated when the air
conditioning switch is
switched ON.)
Air conditioning compressor clutch relay
Function
Item No.
Data reading 49
Data display
Check conditionsAir conditioning switchNormal display
Air condition-
. Engine: idling afterOFFOFF (Compressor
ing compres-warm up clutch non-
sor clutch
activation)
relay status ON
ONKompressorclutch activation)
HARNESS INSPECTION________ --- -__-. -- ~~-
Measure the power supply voltage of
the air conditioning circuit.
. Engine control module connec-tor: Disconnected- Ignition switch: ON+ Air conditioning switch: ON
side connector
AIR CONDITIONING INSPECTION
Refer to GROUP 55-Air Conditioning.
1 TSB RevisionI

FUEL SYSTEM -On-Vehicle Inspection of MFI Components13-289
OPERATION
l The EGR temperature sensor functions to con-
vert the data regarding the temperature of the
EGR gas downstream from the EGR valve to
voltage, and to input that voltage (as signals) to
the engine control module.
lThe 5V power supply within the engine control
module is supplied, by way of the resistance
within the unit, to the EGR temperature sensor;
it passes through the EGR temperature sensor,
which is a type of resistor, and is grounded at the engine control module.
Note that the resistance of the EGR tempera-
ture sensor decreases when the EGR gas vol-
ume increases and the temperature of the EGR
gas increases.
l The EGR temperature sensor terminal voltage
becomes higher when the resistance of the EGR
temperature sensor increases, and becomes lower when the resistance decreases.
Consequently, the EGR temperature sensor
terminal voltage varies in accordance with the
temperature of the EGR gas, becoming lower when the temperature of the EGR gas
in-
creases.
INSPECTION Using Scan tool
Function Item No.
Data reading
43
Data display 1 Inspection conditions1 Engine condition1 Standard valueI
Sensor. Engine: warm upIdling100°C (212°F) or lower
temoerature* Enaine is maintained in Ia &nstant state for 2
minutes or more
. Remove the vacuum
11 7J$lfifiF~ nr lower 1
hose (green stripes) fromthe EGR solenoid and3,500 rpm150°C (302°F) or higher/hlnn-Turbo>plug both the removed
vacuum hose end and
solenoid valve nipple.
HARNESS INSPECTION
Harness side
connector Measure the power supply voltage.
. Connector: Disconnected
. Ignition switch: ON
Voltage
(V)Repair the
Harness side
connector Check for continuity of the ground
circuit.
. Connector: Disconnected
SENSOR INSPECTION Refer to GROUP
l7-Exhaust Gas Recirculation (EGR) System.
Repair theharness.
@El-IIll. q l)
TSB Revision

FUEL SYSTEM -On-Vehicle inspection of MFI Components13-291
INSPECTION
Using Scan tool
Function
Data reading Item No.
11
HARNESS INSPECTION
T
Data display
Sensor de-tection vol-
tage
L
Inspection conditionsEngine conditionStandard value
Engine: warm up When sudden decel-250 mV or lower(Make the mixture leaneration from 4,000 rpmby engine speed reduc-tion, and rich by racing)When engine is sud- 500- 1,000 mVdenly raced
Engine: warm up750 rpm (Idling)(using the oxygen sen-
~~~,s~~~r~hr~~i~t~~~ir’ 6JO;K~~ldling)
also check the condition
of control by the engine
2,000 rpmcontrol module)
400 mV or lower
I(changes) 600-
1,000 mV
connector
Enginecontrol module
harness side
@ ZTE-mector -La
@ El
4 3
-l
g;
@ Harness side
connector
Measure the power supply voltage of
the heated oxygen sensor.
Connector: Disconnected Ignition switch: ON
I II
Check for an open-circuit or a short-circuit to ground, between the enginecontrol module and the heated oxy-gen sensor.
. Heated oxygen sensor connec-
tor: Disconnected103
. Engine control module connec-tor: Disconnected
i
Repair theharness.
Nzm+l)
Check for continuity of the groundcircuit.
. Connector: Disconnected
@fR&eharness.
t
C@rzI-m,
@El-Ground)
1 TSB Revision I ’

13-296FUEL SYSTEM -On-Vehicle
Inspection
of
MFI
Components
INSPECTION
Using Scan tool
Function Item No. Data displayInspection conditionsEngine coolant temperature Standard value1
Data 41;ctJ$onEngine crankingAt 0°C (32”F)*2Approx. 17 ms
readingApprox. 40 ms
At 20°C (68°F)Approx. 38 ms
Approx. 19 ms
At 80°C (176°F)Approx. 9 ms
Approx. 4.5 ms
Function
Datareading
3TE Item No.
41
Data display
$ctX$on
Inspection conditionsEngine condition
Standard value
. Engine coolant tempera-Idling2.4-3.2 ms
ture:1.6-2.6 ms 85-95°C
(185-205°F)
. Lights, cooling fan, electric- 2,000 rpm1.9-2.9
ms
al accessories: OFF1.4-2.2 ms . Transaxle: neutralDuring sudden Increasesracing
+l:The injector activation time indicates the time under the following cond\
itions: a power source voltage of 11V and acranking rpm of 250 rpm or less.*2: 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].
Function Item No.Description Inspection conditionsNormal indication
Actuator test 01No. 1 injector is shut off.
Engine: idling after warmThe idling condition
02No. 2 injector is shut off.?!hut off the injectors inchanges more.
(Either becomes more un-
03
No. 3 injector is shut off.
04
No.4 injector is shut off.
sequence during after
engine warm-up, check
the idling condition.) stable, or engine stalls.)
,d&- A: InjectorNormal wavetormdrive time
HARNESS INSPECTION

@ Harness sideconnector
I
L
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 ofthe resistor.
. Connector: Disconnected. Ignition switch: ON
1 TSB hevision

FUEL SYSTEM -On-Vehicle Inspection of
MFI Components13-299
OPERATION
l The amount of air taken in during idling is
regulated by the opening and closing of the
servo valve located in the air passage that
bypasses the throttle valve.
l The servo valve is opened or closed by the
activation of the stepper motor (incorporated
within the idle air control motor) in the forward
or reverse direction.
TROUBLESHOOTING HINTS
Hint 1: If the number of stepper motor steps increases to
IOO- 120 steps or decreases
to 0 step, the cause may be presumed to be a malfunction of the stepper motor or
damaged or disconnected wiring of the
harness.
Hint 2: If the number of stepper motor steps
deviates from the standard value even
though the results of the checking of the
harness of the idle air control motor and of
the comoonent
itself indicate no abnormal
condition, the cause may be presumed to be one of the following.
INSPECTION
Using Scan tool
lBattery power supply is supplied, by way of the
multiport fuel injection relay, to the coil of the
stepper motor. The engine control module
switches ON the power transistors (located
within the engine control module) in sequential
order, and, when current flows to the stepper motor coil, the stepper motor is activated in the
forward or reverse direction.
(1) Improper adjustment of the standard
idling speed.
(2) Deposits adhered to the throttle valve.
(3) Leakage of air into the intake manifold
from a gasket gap, etc.
(4) Incomplete close contact of the EGRvalve seat.
(5) Incomplete combustion within the
cylinder.
(Malfunction of the spark plugs, the
ignition coil, the iniectors,
the
com- pression
pressure, etc.)
FunctionItem No.Data display Check conditions Load conditionsStandard value
Data reading 45Steppermotor steps. Engine coolant tempera-
. Air conditioning
4-14Step
ture:switch: OFF 85-95°C

(185-205°F)
. Lights, electrical cooling
:$b::pfan and accessories: OFF
. Transaxle: neutral
. Closed throttle switch: ON
- Air conditioning 20-60 Step
switch: ON
(The compressor clutchshould be activated when
the air conditioning switch;J-;;o~P
is switched ON.)* Engine: idling
1;:!,1;:!,
/!-I\/!-I\
f$&$:”f$&$:”
! ,‘,! ,‘,
4);4);
;jj\(Q(j!jGZ-);jj\(Q(j!jGZ-)
lili
q#Q~Hq#Q~HF]F]
ii 2 L J 2 L ~ -0SClllO 4ii 2 L J 2 L ~ -0SClllO 4
NOTE
When the vehicle is new (driven approximately 500 km (300 miles) or l\
ess) the number of steps may be about
30 steps greater than the standard value indicated above.
Using Oscilloscope
(1) Connect the probe to each oscilloscope pick-up point as
shown in the circuit diagram.
(2) Start the engine.
(3) When the air conditioning switch is turned on, the idling speed increases to operate the idle air control. Check theinstantaneous waveform.
NOTE
Keep in mind that the waveform can be observed only
when idle air control is in operation.

r
FUEL SYSTEM -On-Vehicle Inspection
of
MFI Components13-303
INSPECTION
Using Scan tool
Function Item No.
Data reading 44
Data displayInspection conditionsEngine condition Standard value
Ignition
advance
. Engine: warm
. Timing light: set750 rpm (idling)5-15” BTDC
(Use the timing light to
check the actual ignition 2,000 rpm32 - 4 1 “BTDCtiming.)
Oscillo 1
Normal waveform
Oscilio 2
!
1ov --
-
ovNormal waveform
HARNESS INSPECTION
Harness side
connectorE 0-0
J
El0
connectorI
lEnginecontrol
module
harness
sideconnector
Using Oscilloscope
1. Primary signal of ignition coil
(1) Run the engine at an idle revolution speed.
(2) Connect the probe to oscilloscope pick-up point
1 as
shown in the circuit diagram, and check the primary
signal of the ignition coil.
2.Control signal of ignition power transistor
(3) Connect the probe to oscilloscope pick-up point 2 as
shown in the circuit diagram, and check the control
signal of the ignition power transistor.
Measure the power supply voltage ofthe ignition coil.
. Connector: Disconnected. Ignition switch: ON
Voltage (VI
IBattery positive voltageIIIgnitionswitch)
Check for an open-circuit, or a
short-circuit to ground, between the engine
control module and the ignition coil.
* Engine control module connec- tor: Disconnected
* Ignition coil connector: Discon-nected
i
Repair theharness.
N23l3k-m)
TSB Revision