MITSUBISHI GALANT 1989 Service Repair Manual

On-Vehicle Inspection of MFIFUEL SYSTEM VALVE> - Components13-149
a Harness side
connector
--------
m
J-----k
N
qp
CI
F
Check for continuity between the fuel
pump checking terminal and between
the
multiport fuel injection relay ter- minals.
l
Multiport fuel injection relay con-
nector: Disconnected Fipnn~r
the
l Fuel pump connector: Discon-
nected
.-P-” _’ ‘-& harness.
(@m-00,
I9FUOO24
OlA0401
Check for an open circuit, or short-cir-
cuit to ground between the
multiport
fuel injection relay and the fuel pump.
l
Multiport fuel injection relay con-
nectar:
Disconnected
l Fuel pump connector: Discon-
nected
@ Harness sideconnector
Measure the power supply voltage of
the fuel pump.
l
Multiport fuel injection relay con-
nector: Connected
l
Enoine control module connec-
tor: Connected
Engine
1Voltage IV1
cCranking ~8V or more-
I
MultiportI fuel injec-
__, tion relay or
1
engine con-
~
trol
module
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IRacing Iid+: is defective.6FU175.3I
MULTIPORT FUEL INJECTION RELAY IN
-
SPECTION
Refer to P.13-145.

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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1

On-Vehicle Inspection of MFIFUEL SYSTEM VALVE> - Components 13451
Using Oscilloscope
(1) Run the engine at idle speed.
(2) Connect the probe to the osilloscope
pick-up point as
shown in the circuit diagram, and check the wave form.
Regular waveform03AO203
HARNESS INSPECTION
Check for continuity between volume
air flow sensor and
multiport fuel in-
jection relay.
l
Multiport fuel injection relay con-
nector: Disconnected
l Volume air flow sensor connec-
tor: Disconnected
NOTE
Touch the circuit tester probes to
both ends of the harness
a+
OK 121
harness side
connector6FU1953
connector
Check for continuity of the ground-Icircuit.
0 Volume air flow sensor connec-WI+ 131tor: DisconnectedL-l I
OlR0262
/I
module harness
@ Harness sideconnector
= =
6FU1954
0O

K
-I+
Check for broken wire or short-circuit
to ground, between volume air flow
sensor and engine control module.
l Volume air flow sensor connec- tor: Disconnected
l Engine control module connec- tor: Disconnected
El4
Repair the
harness.
(ml-El)
Measure the impressed voltage.
0 Volume air flow sensor connec- tor: Disconnected
l Engine control module connec-
tor: Connected
l Ignition switch: ONconnector
Voltage (V)
4.8 - 5.2
I TSB Revision

13-152FUEL SYSTEM (SOHC-16 VALVE> - %i;:%~spection Of MF’
INTAKE AIR TEMPERATURE SENSORMl3YGAA
Volume air flow sensor
Volume air flow sensor
(built in intake air
(built in intake air
Intake
airtemoerature sensor
Engine control
module connector
I
TemperaturewTemperature1621006142468
@ Volume arr tlowsensor connector [-1 ~$%re
Harness side
connector k
A 72
~o~~~e p-$-J 5v
7FlD&53
6FU1955
OPERATION
TROUBLESHOOTING HINTS INSPECTION
Using Scan Tool
Refer to
P.13-51.
HARNESS INSPECTION @ Harness side
connector
-,T
[
a
1
g@-r.
Check for continuity of the ground
circuit.
l Volume air flow sensor connec-
tor: Disconnected
Repair the
+ harness.
/ (ml-El)
OlRo262 II
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FUEL SYSTEM - ::ii$%tt=pection Of MF’13-153
@ Harness srdeconnector
Check for open circuit or short circuit
to ground, between intake air tempera-
ture sensor and engine control mod-
ule.
0 Volume air flow sensor connec-/
tor: Disconnected
l Engine control module connec-
tor: DisconnectedI Repair th
e
+ harness.
I @El -El)
@ Harness side connector
6FU195C
1
[IMeasure the impressed voltage.n
~
A
0 Volume air flow sensor connec-
tor: Disconnected
l Engine control module connec-
tor: Disconnected
l lqnition
switch: ON
-
Replace
Voltage
(VI1 c#?g -+ zl;;fne
4.5 - 4.9 moaule.
SENSOR INSPECTION Refer to P.13-52.
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On-Vehicle Inspection of MFI13-154FUEL SYSTEM - components
BAROMETRIC PRESSURE SENSOR
MlJYHA4
Barometnc -pressure
sensor
htput Voltage
Barometric pressure
mmHg 760 ~~1551
CR Volume air flowBarometric pressure sensorI I
I-.____A__sensor conneclur
mB Harness sideconnector
,\ , , ,.k ,Im jfl5EL1600
6FU1957
Engine control module connector
7FlfO653
OPERATION TROUBLESHOOTING HINTSINSPECTION
Using Scan Tool Refer to
P.13-53.
HARNESS INSPECTION
@ Harness sideconnector I,?
la
1
gg
n
1Check for continuity of the ground-IIj circuit

.
/ 0 Volume air flo

w
----^- ^^^^^^ibd-b 121IsensorGUI II IGL-tor: Disconnectedw -
I
OlRO262 j
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FUEL SYSTEM - ::~,%~t~pection Of MF’13-155
L-J
2@ Harness side
@ Harness stde
connector Engine control
module harness
side connector
r----l65
mr01AO107
~Check for an open circuit, or a short-
circuit to ground between the engine
:control module and the barometric
pressure sensor.
il Volume air flow sensor connec-
tor: Disconnected
l Engine control module connec-
tor: Disconnected
Measure the impressed voltage of the
barometric pressure sensor.
l Volume air flow sensor connec- tor: Disconnected
l Engine control module connec-
tor: Connected
l Ignition switch: ON
Voltage
(VI
Replace
- the engine 1
control
module.
IOIAO233 I4.8 - 5.2I
Engrne coolant
Engine coolant
@ Equipment temperature sensorside connector
Enginecontrol
module
72
6
3
I fh5v
Engine coolanttemoerature
Engine control module connector
7FW6!53
9FUO106
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13-156On-Vehicle Inspection of MFI
FUEL SYSTEM (SOHC-16 VALVE> - Components
OPERATION
TROUBLESHOOTING HINTS INSPECTION
Using Scan Tool
Refer to
P.13-55.
HARNESS INSPECTION
Harness side
connector
Check for continuity of the ground
circuit.
l Engine coolant temperature sensor connector: Drsconnected
9FUO112
01
OK+ /2/
Repair the
& harness.
i @lz -@i,
r
21t@ Harness sideconnector
2 1
7
Check for open circuit or short-circuit
to ground, between engine coolant
temperature and engine control mod-
!:I->,
OK+ 131
ule.
l Engine coolant temperature
connector: Disconnected
l Engine control module connec-
~ 1 h h L
~
tor: Disconnected$)#!& ” g$jnii
7 7
c
module harness
side connector
9FUO113
3
@ Harness side connectx
Measure the Impressed
voltage.
l Engine coolant temperature sensor
connector: Dlsconnected
l Engine control module connec- tor: Connected
l Ignition switch. ON Replace
& the engine
control ,
I
9FUO114
moaure.
SENSOR INSPECTION
Caution
J
Be careful not to touch the tool against the connector (resin
section) when removing and installing.
(1) Remove engine coolant temperature sensor from the ther- mostat housing.
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FUEL SYSTEM (SOHC-16 VALVE> - ::ii,,k%ti=pec*ion Of MF’13-157
9FUO156
9FUO157
THROTTLE POSITION SENSOR
MinimumMaxlmum
Throttle shaft turning angle162461
(21 With temperature sensing portion of engine coolant tem-
perature sensor immersed in hot water, check resistance
Temperature PC (“F)lResistance (k!S)
0 (32)5.8
I20 (68)~12.4I
I80 (I 76)I0.3I
Engine control module connector
(3) If the resistance deviates from the standard value greatly,
replace the sensor.
INSTALLATION
(1) Apply sealant to threaded portion. Specified sealant:
3M NUT locking Part No. 4171 or
equivalent
(2) Install engine coolant temperature sensor and tighten it to specified torque.
Sensor tightening torque:
20-40 Nm (15-29 ft.lbs.)
(3) Fasten harness connectors securely.
@ Equipment sideconnectorThrottle posltlon sensor
@ Harness srdeconnector
pJ$q]
1
5EL1400
I72-
E
6461
r 1
Engine control module
7FUO672
L
7FUO653
1 TSB Revision

On-Vehicle Inspection of MFI
13-158FUEL SYSTEM (SOHC-16 VALVE> - Components
OPERATION
aThe throttle position sensor converts the throttle position opening into a voltage and inputs it to the
engine control module, which
then controls
the
fuel injection, based on the input signal.
l The
5V power in the engine control module is
supplied to the throttle position sensor. It flows
through the resistor in the sensor and is then
grounded in the engine control module.
lAs the throttle valve shaft rotates from the idle position to wide open position, the resistancebetween the variable resistor terminal of the
throttle position sensor and the ground terminal increases. As a result, the voltage at the throttle
position sensor variable resistance terminal also
increases.
INSPECTION
Using Scan Tool TROUBLESHOOTING HINTS
Hint 1: The throttle position sensor signal is more important in the control of automatic trans-
axle than in the engine control. Shifting
shock and other troubles will be caused if
this sensor is faulty.
Hint 2: If the output voltage of the throttle position
sensor is out of specification, adjust the
sensor and check the voltage again.
If there is an evidence of disturbed fixed SAS
setting, adjust the fixed SAS.
Function item No.Data displayCheck conditionThrottle valve Standard value
Data14Sensor Ignition
switch: ON At idle position 300 - 1000 mV
readingvoltage
Open slowlyIncreases with valve
opening
Open widely 4,500
- 5,500 mV
HARNESS INSPECTION
-
i1
@ Harness sideconnector
Check for continuity of the ground
circuit.
l Throttle position sensor connector: Disconnected
Repair the
harness.
(ml-m
3 Harnessside connetor
P
ECMharness sidef connector
Check for an open-circuit, or a short-
circuit to ground between the engine
control module and the throttle posi-
tion sensor.
l Throttle position sensor connector:
Disconnected
l Engine control module connec-
tor: Disconnected Repair the
harness. @El

- El)
(@III-ElII
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