1989 MITSUBISHI GALANT Service Repair Manual

FUEL SYSTEM (SOHC-16 VALVE> - :::;::tt?ction Of MF’13-147
FUEL PUMPM13YEAB
6FUO985-
@ Equipment srdeconnector
@ Harness sideconnectorI
Ignition switch (IG)
Multiport
fuel
@I Equipment sideconnector
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Fuel pump-I
@ Harness sideconnector
Engine COntrOl module A 8
7Fuom 6FU1951
OPERATION
a The fuel pump is driven when the engine i
s
cranking and while the engine is running.
lWhen the engine is cranking and while the engine
is running, the engine control module turns the
power transistor ON to supply power to the
multiport fuel injection relay coil. This causes
the
multiport fuel injection relay switch to turn
ON, and current is supplied from the ignition
switch via the multiport
fuel injection relay
switch to drive the fuel pump.
INSPECTION Using Scan Tool Refer to
P.13-46.

On-Vehicle Inspection of MFI
13-148FUEL SYSTEM (SOHC-16 VALVE> - Components
HARNESS INSPECTION
@ Harness sideconnector
Check for continuity of the fuel pump
grounding line.
l Fuel pump connector: Discon-
netted
Repair th

e
4 harness
~

@El-Ground)
Check for open-circuit or short circuit
between the fuel pump and the fuel
pump drive terminal.
l Fuel pump connector:
Drscon-
nettedl Multiport fuel injection relay con- nectar:
Disconnected
I/
2 .lr/ Repair theL^Srr,-..-r
P
9vh
connector T-y 6FU1238!
I
@ Harness srdeconnector
Measure the power supply voltage of
the
multiport fuel injection relay.
l
Multiport fuel injection relay con-
nector: Disconnected
r
9FUOO23;
IIIEngine controlCheck for an open circuit, or short-cir-
cuit to ground between the
multiport
fuel injection relay and the enginecontrol module.
l
Multiport fuel injection relay con-
nector: Disconnected
l Engine control module connec-
tor: Disconnected!
Repair the
+ harness. ~

@H-B)
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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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