1989 MITSUBISHI GALANT sensor

13-52 FUEL SYSTEM - On-Vehicule Inspection of MFI Components
Consequently, the intake air temperature sensor
terminal voltage varies in accordance with the
temperature of the intake air, becoming lower
when the temperature of the intake air in-
creases. TROUBLESHOOTING HINTS
Because the intake air temperature sensor detects
the temperature of the intake air in the air cleaner, it
indicates a temperature different than the
tempera-
ture of the outside air when the engine is running.
INSPECTION
Using Scan tool
Function Item
No.
Data reading 13 Data display
Sensor de-tectlontemperature
connector
-,-S=
[
a
ry:
EQO
n
OlRO262
Check conditions
Ignition switch: ON
Or, engine running Intake air temp.
At
-20°C (-4°F)
At 0°C (32°F)
Standard value -20°C
0°C
IAt60~) I 80°CI
HARNESS INSPECTION
I
@ Harness sideconnector 8 0-0
Jill
I54
T
Volume air flowsensor side connector
Check for continuity of the ground
circuit.
. Connector: Disconnected
/-
/OKcl2
--/
Repair theharness.
@El-lT$lH)
IMeasure the power supply voltage.
Connector: Disconnected Ignition
switch: ON
IASTOPVoltage (V)
1 4.5-4.9 1
SENSOR INSPECTION
(1) Disconnect the volume air flow sensor connectors.
(2) Measure resistance between terminals @
and
@.
6FUO622
Temperature “C (“F)
0(32)
20(68)
80 (176)
Resistance (kS2)
6.0
2.7
0.4A
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FUEL SYSTEM VALVE>- On-Vehicule Inspection of MFI Components13-53
BAROMETRIC PRESSURE SENSOR
Volume air
Barometric.pressure
sensor
lutput Voltage ECl53.
Barometnc
pressure
mmHg 760 ~~1551
(3) Measure resistance while heating the sensor using a hair
drier.
Temperature
“C (“F)Resistance (kQ)
HigherSmaller
(4) If the value deviates from the standard value or the resist-
ance remains unchanged, replace the volume air flow sen-
sor assembly.
MlBYHAA
@ Volume air flow sensor connector
@ Harness sideconnector
t
113 j23 b ‘I 24j i
IEngine control module
6FU1293 Enaine
control module connector
OlL0838
OPERATION
l The barometric-pressure sensor functions to
convert the barometric pressure to voltage, and
to input that voltage (as signals) to the engine control module.
The engine control module, based upon those signals, then corrects the amount to fuel injec-
tion, etc.
l
The 5V power supply within the engine control
module is supplied to the barometric-pressure
sensor; it passes through the circuitry within the
sensor, and is grounded at the engine control
module.
l The barometric-pressure sensor output voltage
is sent to the engine control module in propor-tion to the barometric pressure (absolute pres-
sure).
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13-54 FUEL SYSTEM - On-Vehicule Inspection of MFI Components
TROUBLESHOOTING HINTS Hint 1: Hint 2:
If there is a malfunction of the barometric-pressure If, during high-speed driving, there is a noticeable
sensor,
driveability of the vehicle will become worse sharp drop of the displayed pressure of th
e
barometric-rxessure sensor, check for clogging ofparticularly at hig’h altitude

.
the air cleaner.
INSPECTION Using Scan tool
AltitudeStandard valueICheck conditions
Item No. Data display
25Sensor detec-
tion pressure
Function
Data reading
Ignition switch: ON
At 0 m (0 ft.) 760 mmHg
At 600
m(1,969ft.j710 mmHg
I
At 1,200 m660
mmHg(3,937
ft.)
At 1,800
m(5,906 ft.) 610 mmHgI
HARNESS INSPECTION
Check for continuity of the ground
circuit.
. Connector: Disconnected
connector
L,?
la
Fi
gg-CI
e
Repair the
harness.
KBEil-IBHZI)
Measure the power supply voltage of
the barometric oressure
sensor.
. Connector: Disconnected
. Ignition switch: ON
Harness side
connector
Check for an open-circuit or a short-circuit to ground between the engine
control module and the barometric pressure sensor.
f Volume air flow sensor connector: Disconnected
Engine control
module harness
@ Harness sideside connector
Engine control module connec-
tor: Disconnected Repair the
harness.
ozsEl-~)
1 TSB Revision

FUEL SYSTEM -On-Vehicule Inspection of MFI Components13-55
ENGINE COOLANT TEMPERATURE SENSORMl3wAB
Coolant-
tempera&Coolant temperature
Harness side Component sideEngine coolant temperature sensorIconnector
connectorI -
15EL12011I IA14”24A20
Engine
control
module
If9-3 5v
6FU1239
OPERATION
l The engine coolant temperature sensor func-
tions to convert the barometric pressure to vol-
tage, and to input that voltage (as signals) to the
engine control module.
The engine control module, based upon those
signals, regulates the amount ot fuel injection
and the fast-idling speed when the engine is
cold.
l The 5V power supply within the engine control
module is supplied, by way of the resistance
within the unit, to the engine coolant tempera-
ture sensor; it passes through the engine
coolant temperature sensor, which is a type ofresistor, and is grounded at the engine control
module.
TROUBLESHOOTING HINTS
if, during engine warm-up, the fast-idling speed is
not correct, or black smoke is emitted the problem
is usually a malfunction of the engine coolant tem-
perature sensor. Note that the resistance of the engine coolant
temperature sensor decreases when the tem-
perature of the coolant increases.
l The engine coolant temperature sensor terminal
voltage becomes higher when the resistance of
the engine coolant temperature sensor in-
creases, and becomes lower when the resist-
ance decreases. Consequently, the engine
coolant temperature sensor terminal voltage va- ries in accordance with the temperature of the
coolant, becoming lower when the temperature
of the coolant increases.
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13-56 FUEL SYSTEM - On-Vehicule Inspection of MFI Components
INSPECTION
Using Scan tool
FunctionItem No.
Data reading
-*LI
Data display
Sensor de-
tection
temperature
HARNESS INSPECTION
connector OlLO461Check conditions
Ignition switch: ON
Or, engine running Coolant temperature
Standard value
At
-20°C (-4°F)-20°C
At 0°C (32°F)0°C I
At
20°C (68°F)20°C
connector - Ic
OIL0463L
-16R1251
Temperature “C (“F)Resistance (kS2)
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.
J
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At 40°C (104°F)40°C
At 80°C (176°F)80°C
1
Check for continuity of the ground
circuit.
. Connector: Disconnected
Repair the
harness.
b&XII-@.
lm
Measure the power supply voltage.I. Connector: Disconnected
Ignition switch: ONVoltage
(VI
SENSOR INSPECTION
(1) Remove engine coolant temperature’ sensor from the
intake manifold.
(2) With temperature sensing portion of engine coolan
t
temperature sensor immersed in hot water check resist-
ance.

FUEL SYSTEM - On-Vehicule Inspection of MFI Components13-57
INSTALLATION
(1) Apply sealant
3M
NUT locking No.41 71 or equivalent to
threaded portion.
(2) Install engine coolant temperature sensor and tighten it to specified torque.
Sensor tightening torque:
20-40 Nm (15-29 ft.lbs.1
(3) Fasten harness connectors securely
THROTTLE POSITION SENSOR

-(‘Throttle position a\“ ’
6FUO637
TerminalvoltageWI
L
Minimum Maximum01 LO838Throttle shaft turning angle162461
Component side
Throttle position sensor
connector
olAO336
Engine control module connector Ml3YJAE
OPERATION
l
The throttle-position sensor functions to convert0When the throttle valve shaft is rotated all the
the degree of opening of the throttle valve to way from the idling position to the fully open
voltage, and to input that voltage (as signals) to position, the resistance between the throttle-
the engine control module. The engine control position sensor’s variable-resistapce
terminal
module, based upon those signals, then regu-
and the ground terminal also increases in
lates the amount of fuel injection, etc. accordance with that rotation, and, as a result,0The 5V power supply within the engine control
the voltage of the throttle-position sensor’s
module is supplied to the throttle-position sen-
variable-resistance terminal also becomes high-
SOT after which it passes through the
resistanceer in
accordance with that rotation.
w&in the sensor and is grounded at the engine
COMO\
module.
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13-58 FUEL SYSTEM -On-Vehicule Inspection of MFI Components
TROUBLESHOOTING HINTS
Hint 1:Hint 2:
The signals of the throttle-position sensor are more If the voltage of the throttle-position sensor deviates
important for control of the automatic transaxle than from the standard value, check once again after
for control of the engine; shifting “impact shocks” making the throttle-position sensor adjustment.
are produced if there is a malfunction of the
throttle-position sensor.
INSPECTION
Using Scan tool
Function/ Item No.1 Data display 1 Inspection conditions1 Throttle valve1 Standard value
Data reading 14 Sensor
vol-tageIgnition switch: ON held
for 15 sec. or more
HARNESS INSPECTION
E q-0
JJ ~
@ Harness side0
connector
@ Harness sideconnector
Harness side
connector
Measure the power supply voltage of
the throttle position sensor.
. Connector:’ Disconnected
. Ignition switch: ON
Check for continuity of the ground
circuit.
Connector: Disconnected
Repair the
harness.
bZilZl-m* &I)
Check for an open-circuit, or a short-
circuit to ground, between the engine
control module and the throttle posi-
. Throttle position sensor connector: Engine control module connector:
Disconnected Repair the
harness.
Fi&TUI-mj
01103611
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FUEL SYSTEM -On-Vehicule Inspection of MFI Components13-59
Re
Blu
THROlTLE POSITION SENSOR
SENSOR INSPECTION
(1) Disconnect the throttle position sensor connector, and
connect the special tool (Test harness) between the
disconnected connectors.
(2) Measure the resistance between terminal @ (black clip of
special tool) and terminal @
(red clip) of the connector on
throttle position sensor side.
Standard value: 3.5-6.5
kS2
(3) Measure the resistance between terminal @ (black clip of
special tool) and terminal @
(blue clip).
Open the throttle valve slowly Resistance should vary from
from idle position to fully open approx. 0.5 kQ to 3.5-6.5
kQ
position
smoothly in proportion to
change in throttle valve opening
(4) If the resistance does not conform with specification, or does not vary smoothly, replace the throttle position
sensor.
Throttle position sensor installation torque: 1.5-2.5 Nm (1.1-1.8
ft.lbs.1
M13YJAF
Component srde@ connectorThrottle posltlon SensorI
Harness side@ connector
m 1,. I,, .I,, I,, It,
~$-T~ ;I
TerminalvoltageIV1
Engine control module connector
Minimum
Maximum01 LO.0838Throttle shaft turning angle102461
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