engine MITSUBISHI GALANT 1989 Service Repair Manual

FUEL SYSTEM - Service Adjustment Procedures
13-249
<1989 models> /zz Throttle position
(2) If a scan tool is not used, perform the following operation.,-
~1989 models> @ Disconnect the throttle-position sensor connector,
and connect the special tool (test harness) between the
disconnected connectors.
:1989 models>@Connect a digital-type voltmeter between the @ termin-
al (red clip, sensor ground) and the @I terminal (blue clip,
sensor output) of the throttle-position sensor connec-
tor.
Blue
clip
@ Disconnect the
throttle.position sensor connector and
use the special tool (test harness set) between the
disconnected connector. @ Connect a digital type voltmeter between terminal @
(sensor output) of the throttle position sensor and
terminal
@ (sensor ground).
(3) Switch ON the ignition switch. (Do not start the engine.)
(4) Check the throttle-position sensor’s output voltage.
When a scan tool is used, select Item
No.14 to read the
throttle position sensor output voltage.
Standard value:
0.48-0.52 V.
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FUEL SYSTEM -On-Vehicle Inspection of MFI Components13-251
ON VEHICLE INSPECTION OF MFI COMPONENTS
COMPONENT LOCATION
4 QCiW41QQWPQWQ
I l-+-Y8’
-,..I- - IIII\< I IJ I
/ \lI/--Gl/
El q
I &
q
‘\
P P
6EM0166
MIBYA-A
6FUO843
NameSymbol
NameSymbol
Air conditioning compressor clutch relayKidle air control motor (stepper motor)C
Air conditioning switch0Ignition coil (ignition power transistor)G
Closed throttle position switch (fixed SAS)EIgnition timing adjustment terminalR
Crankshaft position sensor and camshaft posi-HInjectorJtion sensor- Knock sensorYData link connectorS~Multiport
fuel injection relayNEngine control moduleQ-Park/neutral position switch vEngine coolant temperature sensorF-Power steering pressure switchUEGR solenoidL- Throttle position sensorDEGR temperature sensorM-Turbocharger waste gate solenoidXEvaporative emission purge solenoidI~ Vehicle speed sensor (reed switch)PFuel pressure solenoidwVolume air flow sensor (incorporating intakeFuel pump check terminalTair temperature sensor and barometric pres-B- sure sensor)
Heated
oxygen sensorIA I-
NOTE
The “Name” column is arranged in alphabetical order.II TSB
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FUEL SYSTEM - On-Vehicle Inspection of MFI Components13-255
COMPONENTS INSPECTION PROCEDURE-
Using Scan ToolMlsYsAGa
Refer to P.13-41.
POWER SUPPLY AND IGNITION SWITCH-IG
zT=f?Qjkeinjection relay
contrc! qcdule ,6A04,,-
----_OFF/ (IN
t5
’ i
4
-
‘OWE;uppl-
Ignition switch [IG,]
Component
side
connect<
763 66.----
1 6FU1331, )r
Ml3YcAB
Harness
@ side connector
01 LO838
OPERATION
l While the ignition switch is ON, battery power
supply is supplied to the engine control module,
injectors, volume air flow sensor, etc.
l When the ignition switch is switched ON, cur-
rent flows from the ignition switch, via the mul-
tiport
fuel injection relay coil to ground.
INSPECTION
Using Scan tool As a result, the
multiport fuel injection relay
switch is switched ON, and power is supplied,
by way of the multiport fuel injection relay
switch, from the battery to the engine control
module.
Function
Data reading Item No.
Data display Check conditionsStandard value
16
Engine control module power- Ignition switch: O
N
Battery positive voltage
supply voltage
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HARNESS INSPECTION
Engine control
module harness
1-OlLO421
Measure the ignition switch terminal
input voltage.
. Engine control module connector:
Disconnected. Ignition swatch: ON
13-256FUEL SYSTEM -On-Vehicle Inspection of MFI Components
Repair theharness.
(Ignition
switch -
Ilrol) @ Harness side
connector
Measure the power supply voltage ofthe multioort fuel iniection relav.
. Connector: Disconnected
Voltage (V)
IBattery positive voltageI
Repair theharness.
(Batter-y-
@@I)
connector
Engine controlmodule harnessCheck for an open-circuit, or a short-circuit to ground, between the engine
control module and the multiport fuelinjection relay.
. Engine control module connec-tor: Disconnected. Multiport fuel injection relay con-nectar: DisconnectedRepair theharness. 7FUO467
alJ*:
k!ii
054 3 2

-
109
9 7 6 Engine control
module
harnessside connector
@ Harness sideconnector
Check for an open-circuit, or a short-circuit to ground, between the engine
control module and the multiport fuelinjection relay.
.
Multiport fuel injection relay con-nector: Disconnected
@--A
. Engine control module connec-tor: Disconnected Repair the-+ harness.
@@I~ El-@?J. 11071)
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FUEL SYSTEM -On-Vehicle inspection of MFI Components13-257
OlLO521
01
LO220
fx!l
.‘,~‘,_C;:i2J,‘:,
OlLO222
1J 7FUO470
1MULTIPORT FUEL INJECTION RELAY INSPECTION
(1) Remove the multiport fuel injection relay.
(2) Use jumper wires and connect
multiport fuel injection relay
terminal
@I to the battery 0 terminal and terminal @I to the
battery 0 terminal.
Caution
Be very careful when connecting the jumper wires because the relay will be damaged if a mistake is made
with the contact terminals.
(3) With battery
0 terminal jumper wire connected and dis-
connected, measure the voltage at multiport fuel injection
relay terminals @ and 0.
(4) Use jumper wires to connect multiport fuel injection relay
terminal
@I to the battery 0 terminal and terminal @ to the
battery 0 terminal.
(5) Disconnecting the jumper wire on the terminal 0 side of
the battery, check whether or not continuity exists across
terminals
@ and @ of the multiport fuel injection relay.
Continuity between terminals 0-0
(6) Use jumper wires and connect multiport fuel injection relay
terminal
@ to the battery 0 terminal and terminal 0 to the
battery 0 terminal.
(7) With the battery 0 terminal jumper wire connected and
disconnected, measure the voltage at multiport fuel injec-
tion relay terminal
0.
Jumper wireTerminal Voltage @
ConnectionBattery positive voltage
Not connected OV
(8) Replace the multiport fuel injection relay if faulty
ENGINE CONTROL MODULE POWER GRtXJNla
Refer to P.13-45.
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k.
13-258FUEL SYSTEM - On-Vehicle Inspection of MFI Components
FUEL PUMP Fuel pump
check terminal
-I--
-
Ignition switch
[r
Ignition switch [IGI @
Component side
connector @ Harness side
Iconnecto

r
Fuel pump connector
I
,- __ _ /OlAO488
-T
IComponent side
connector
@
h 56 @
Harness side
1
v y
connector
-NC-
lrll
0
1-z
Fuel pump checkA 13 terminal harness
side-1 connector
I Engine
control
module
connector
Engine control module
6FU1295
01 LO838
OPERATION
l
Activates the fuel pump during engine cranking
and while the engine is running.
l When the ignition switch is set to the START
position, the current flows, by way of the multi-
port fuel injection relay coil, from the ignition
switch to ground. As a result, the multiport fuel
injection relay switch is switched ON, and the
power for activation of the fuel pump is sup-
plied, by way of the multiport fuel injection relay
switch, from the battery to the fuel pump.
lWhile the engine is running, the engine control module switches ON the power transistor, after
which current flows to the multiport fuel injec-
tion relay coil, and the power for activation of
the fuel pump is supplied to the fuel pump.
lWhen the multiport fuel injection relay switch is
switched ON, battery voltage is also applied to
the engine control module, and so the engine
control module detects the fact that the power
for activation of the fuel pump is being supplied
to the fuel pump.
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FUEL SYSTEM -On-Vehicle lnwection of MFI Components13-259
INSPECTION
Using Scan tool
Actuator test
Item No.
07
Actuation1 Inspection conditions 1 Descriotion1 Normal condition
Actuates fuel . Engine cranking
Hold the return hose Pulsation can be felt.pump, circu-. Fuel pump forcedbetween two fingerslating fuel.
activation so as to feel the
The inspectionpulsation of the flow-
should be conducted ing of fuel.
for both of the above
conditions. Listen to the pumpPump sound can be
sound at a place near
heard.the fuel tank.
iCTlON
TGrrW’-rTTrrrrrrrrrrrrrrrrrrri 1 SAL TCheck the fuel pump._---__. Apply battery voltage to the check-ing terminal and operate the pump.
@ Harnessconnector
connector 1
sideI_
Check the ground circuit of the fuel
m-m.Connector: Disconnected
Repair theharness.
if?%d
Check for continuity between the fuel
pump and the checking terminal.
Repair theharness.
CW-
Ml)
Check for continuity between the
checking terminal and the enginecontrol module, and between themultiport fuel Injection relay termi-nals.
* Multiport fuel injection relay con-nector: Disconnected- Engine control module connec-tor: Disconnected
- ;~-:edPumpconnector: Discon-
Repair theharness.
@O-00OIHl3)
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13-260FUEL SYSTEM -On-Vehicle Inspection of MFI Components
!5J
@ Harness srdeconnector
7FUO474
Harness srdc@ connector
Engine control
module harness
side connector
7FUO475
7FUO476
@Harness side
I7FllO477
Measure the power supply voltage ofthe multiport fuel injection relay ignition switch.
Connector: Disconnected
. Ignition switch: START
(@a whenchecked). Ignition switch: ON (@@ when
Check for an open-circuit, or a short-circuit, to ground between the multi-port fuel injection relay and the en-gine control module.
. Multiport fuel injection relay con-nectar: Disconnected
. Engine control module connec-
tor: Disconnected Repair the
harness.
uziul-8)
Check for continuity, of the groundcircuit.
. Connector: Disconnected.
cl8
Repair theharness.
%ih,
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Check for an open-circuit, or a short-circuit to ground, between the multi-port fuel injection relay and the fuel
pump.- Multiport fuel injection relay con-nector: Disconnected
- nf;;;edw-wconnector: Discon-
MULTIPORT FUEL INJECTION RELAY IN
-
SPECTION
Refer to P. 13-257.

FUEL SYSTEM -On-Vehicle inspection of MFI Components13-261
VOLUME AIR FLOW SENSORMlWFAAs
/
side
@Harness side connector
I@ Harness sideconnector
Fnnine control module connector
Multiport fuel
The area enclosed with :I: is injection relay
applicable only for Turbo vehicle.
I

@I Component connector (Filter reset circuit)
Engine control module
6FU1537
Intake air amount (Wsec)
162451
OlLO838
OPERATION
l The volume air flow sensor is incorporated
within the air cleaner; it functions to convert the
amount of engine air intake to pulse signals of a
frequency proportional to the amount of engine air intake, and to input those/signals to the en-
gine control module. The engine control module
then, based upon those signals, calculates the
amount of fuel injection, etc.
TROUBLESHOOTING HINTS
HINT 1:
If the engine sometimes stalls, try starting the en-
gine and shaking the volume air flow sensor har-
ness.
If the engine then stalls, incorrect or improper con-
tact of the volume air flow sensor connector is the
probable cause.
Hint 2:
If, when the ignition switch is switched ON (but the
engine is not started), the volume air flow sensor
output frequency is any value other than zero, a
malfunction of the volume air flow sensor or of the
engine control module is the probable cause.
Hint 3:
If idling is possible even though the volume air flow
sensor output frequency is deviated from the
stand-
l The power for the volume air flow sensor is supplied from the
multiport fuel injection relay
to the volume air flow sensor, and is grounded
at the engine control module. The volume air
flow sensor, by intermitting the flow of the
5V
voltage applied from the engine control module,
produces pulse signals.
ard value, the cause is usually a malfunction other
than of the volume air flow sensor. Examples:
(1) The flow of air within the volume air flow sensor
is disturbed. (Air duct disconnection or clogged
air cleaner element)
(2) Incomplete combustion within a cylinder.(Malfunction of spark plugs, ingnition coil, injec-
tors, compression pressure, etc.)
(3) Air is taken into the intake manifold through a
leaking gasket, etc.
(4) Incomplete close contact of the EGR valve seat.
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13-262FUEL SYSTEM - On-Vehicle Inspection of MFI Components
INSPECTION
Using Scan tool
1 Data 12reading
L
Data displayInspection conditions
Sensor de-. Engine coolanttection airtemperature: 85-95°Cvolume (fre-(185-205°F)quency) .Lights, cooling fan, elec-trical accessories: OFF. Transaxle: neutral (PJTmodels: “P” range)
Engine condition
Idling
2,000 rpm
Racing
Standard value 25-50
Hz 30-50 Hz
60-90 Hz 50-80 Hz
Frequency increases as
racing rpm increases.
NOTEThe 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].
i
Regular waveform03AO203
HARNESS INSPECTION 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.
Measure the terminal voltage.
. Connector: Disconnected
. Ignition switch: ON
connectorOlMaa
Measure the power supply voltage.
. Connector: Disconnected
. Ignition switch: ON
Harness side
connectorthe multiport fueinjection relay.
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