1989 MITSUBISHI GALANT engine coolant

13-16
FUEL SYSTEM - Troubleshooting
FAILSAFE/BACK-UP FUNCTIONS LIST
If trouble with any major sensor is detected by the on-board diagnostic,\
the vehicle will be kept in the safe
driving conditions according to the preset control logic.
Trouble item Control content for trouble
Volume air flow Fuel injection timing and ignition timing are determined according to th\
e throttle position
sensor sensor
(TPS) and engine revolution speed signal (crankshaft position sensor signal)\
.
Intake air temperature The control is executed with the suction air temperature regarded as
25°C (77°F).
sensor
Throttle position The fuel injection rate is not increased for acceleration according to t\
he throttle position
sensor
(TPS)sensor signal.
Idle speed control After the idle speed control motor plunger is driven and contracted, the\
idle revolution speed
motor position sensor is not controlled.
Engine coolant The control is executed with the engine coolant temperature regarded as \
8OO.C (176°F).temperature sensor (Even if the sensor signal becomes normal again, the control is continued
until the ignltlon
switch is turned off.)
Camshaft position Simultaneous injection of fuel is executed for all cylinders. (In this \
case, the
No.1 cylinder top
sensor dead center is not detected at all after the ignition key is turned on.)\
Barometric pressure The control is executed with the pressure regarded as 760 mmHg
(30
in.Hg).
sensor
Oxygen sensor Closed loop control of the air/fuel mixture ratio is not executed.
i
READ OUT OF DIAGNOSTIC TROUBLE CODE
Precautions for operation
(1) When battery voltage is low, no detection of failure is possible. Be sure to check the battery for voltage and
other conditions before starting the test.
(2) On-board diagnostic item is erased if the battery or the engine control module connector is discon-
nected. Do not disconnect the battery before the di-
agnostic result is completely read.
Using Scan Tool
(1) Switch OFF the ignition switch.
(2) Connect the power-source terminal of the scan tool to the
cigarette lighter socket.
(3) Connect the scan tool to the data link connector. (4) Turn ignition switch to ON.
(5) Using the scan tool, read out and make a note of the
on-
board diagnostic output.
(6) Refer to the diagnostic chart, and repair the indicated loca-
tion of malfunction.
(7) Erase the diagnostic trouble code. (Refer to
P.13-17.)
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FUEL SYSTEM - Troubleshooting 13-17
\ I\-\\\\\\6FUO807
Using Voltmeter
(1) Connect an analog-type voltmeter between the ground/
terminal and the on-board diagnostic output terminal of the
data link connector.
(2) Set the ignition switch to the “ON” position.
(3) Make a note of the pattern of the on-board diagnostic out- put indicated by the voltmenter’s indicator.
(4) Refer to the diagnostic chart, and repair the indicated loca- tion of malfunction.
(5) Erase the diagnostic trouble code.
On-board
diagnostic
output
terminal
LGround
EbLbtR MEMORY OF DIAGNOSTIC TROUBLE
If the Scan Tool is Used
Connect the scan tool to the data link connector, and then
erase by following the steps below.)
(1) To erase diagnostic trouble code for the engine coolant
temperature sensor or idle speed control motor positionsensor, first turn the ignition switch OFF once and then ON
(2) EE?$t
“4. SPECIAL TEST” of the scan tool’s function-select
menu.
(3) Then select item No.5, “ERASE DIAG.“.
(4) If “ERASE DIAG. CODE?” is displayed, press the “YES” k\
ey.
(5) Input ID code “19”.
(6) When “FINISHED ERASING DIAG. CODE” is displayed,> Ipress the “CLEAR” key.
(7) Read out the on-board diagnostic output and check to be
sure that the correct code is being output.
If the Scan Tool is not Used
(1) Turn the ignition switch to OFF.
(2) Disconnect the ground cable from the battery terminal forten seconds or longer, and then reconnect it.
(3) Read out the on-board diagnostic output and check to be
sure that the correct code is being output.
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13-32
FUEL SYSTEM - Troubleshooting/Service Adjustment Procedures
FUEL TANK AND FUEL LINEMlBEAAA
Symptom Probable cause Remedy
Engtne malfunctions
Bent or kinked fuel pipe or hose Repair or replace3ue to insufficient fuel
SUPPlYClogged fuel pipe or hoseClean or replace
Clogged fuel filter or in-tank fuel filter Replace
Water in fuel filter Replace the fuel filter or clean the fuel tank
and fuel line
Dirty or rusted fuel tank interior Malfunctioning fuel pump
(Clogged filter in the pump) Clean or replace
Replace
Evaporative emission Mispiping of vapor line
Correct
control system malfunc-
tions (When fuel tank Disconnect vapor line piping joint Correct
filler tube cap is re- moved, pressure releas-
Folded, bent, cracked or clogged vapor line Replace
ng noise is heard) Faulty fuel tank filler tube cap
Malfunctioning fuel tank pressure control
valve Replace
Replace
LL
m ~~ : Paper clip-
F l!;“I /yFp- -
izd--_7-01
A0086SERVICE ADJUSTMENT PROCEDURES
CURB IDLE SPEED INSPECTION
MlBFHAFt
(1) The vehicle should be prepared as follows before the inspection.
lEngine coolant temperature: 85-95°C (185-203°F)
l Lights, electric cooling fan and accessories: OFF
l Transaxle: Neutral
(P for vehicles with an automatic
transaxle)
(2) Connect a tachometer or connect the scan tool to the data
link connector.
NOTE
Refer to
P.13-33 for information concerning connection Of
a tachometer.
(3) Set a timing light in position.
(4) Ground the terminal for adjustment of ignition timing.
(5) Start the engine and let it idle.
(6) Check whether or not the ignition timing is the standard
value; if not, adjust.
Standard value:
5”BTDC + 2”
(7) Stop grounding the terminal for adjustment of ignition timing. .
(8) Let the engine idle for two minutes.
(9) Check the idling rpm.
Curb idle speed:
7502 100 rpm
NOTE
The idling rpm is automatically regulated by the idle-speed control system.
1
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FUEL SYSTEM -Service Adjustment Procedures 13-33
For a female
pin
For a male pin
(insert at side (Insert at lock tab side.,
opposite from lock tab.)
OlLO246
(10)lf not within the standard value range, refer to the CHECK
CHART CLASSIFIED BY PROBLEM SYMPTOMS and check the
MFI component.
BASIC IDLE SPEED ADJUSTMENT
MlBFHBA
(1) The vehicle should be prepared as follows before the inspection and adjustment.
l Engine coolant temperature:
85-95°C (185-205°F)
l Lights, electric cooling fan and accessories: OFF
l Transaxle: Neutral
(P for vehicles with an automatic
transaxle)
(2) Slacken the accelerator cable enough.
(3) Connect the scan tool to the data link connector (white).
(4) If the scan tool is not used, follow the steps below.
@I Insert a paper clip (from the harness side) into the l-pin connector shown in the figure at the left.
Take care not to disconnect the connector.
Caution
The paper clip should be inserted between the
terminals as shown in the figure at the left., @ Connect a primary-voltage-detection type of tacho-
meter to the paper clip.
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FUEL SYSTEM -Service Adjustment Procedures 13-35
(14)Adjust the play of the accelerator cable. (Refer to P.13-
329.)
(15)Connect the idle-speed control motor’s connector.
(16)Adjust the throttle-position sensor.
(17)Start the engine again and let it run at idle speed for about
ten minutes; check to be sure that the idling condition is
normal.
THROTTLE BODY (THROTTLE VALVE AREA)
CLEANING
MllFlCK
(1)Start the engine and warm it up until the temperature of the
engine coolant reaches
80°C (176°F) or higher; then stop
the engine.
(2) Disconnect the air intake hose at the throttle body side.
(3) Spray cleaning liquid (from the intake port of the throttle body) onto the valve, and then leave as is for about fiveminutes.
(4) Start the engine and race it a few times; then let it run at idle speed for about one minute.
NOTE
If the engine idling speed is unstable (or the engine stalls),
let the engine run with the throttle valve slightly open.
(5) If deposits are not removed from the throttle valve, repeat steps (3) and (4).
(6) Connect the air intake hose.
(7) Using the scan tool, erase the diagnostic trouble code, or disconnect the battery’s ground cable for ten seconds orlonger and then reconnect it.
(8) Adjust the basic idle speed (engine speed adjusting screw). (Refer to
P.13-33.)
(9) Adjust the throttle position sensor.
-rottle position ” ynsor connector
(2) If a scan tool is not used, perform the following operation.
< 1989 models> @ Disconnect the throttle position sensor connector and
use the special tool (test harness) between the discon-
nected connector.
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THROTTLE POSITION SENSOR ADJUSTMEiW&
Caution
The adjustment of the throttle-position sensor should be
made after completion of the basic idle-speed adjustment.
(1) Connect the scan tool to the data link connector (white).
,

13-38
FUEL SYSTEM - On-Vehicule inspection of MFI Components
ON-VEHICLE INSPECTION OF MFI
COMPONENTS
COMPONENT LOCATION
Ii111 I‘I 1 II
bEM0148
6FUO843
M?BYA-
Name Symbol Name
Symbol
Air conditioning compressor clutch relay
JIgnition coil (ignition power transistor)F
Air conditioning switch 0Ignition timing adjustment terminalR
Crankshaft position sensor and camshaft posi- InjectorIGtion sensor-Multiport fuel injection relayN
Data link connectorS - Oxygen sensor
A
EGR solenoid
K-Park/neutral position switch M
EGR temperature sensor
L-Power steering pressure switchU
Engine control moduleQ- Throttle position sensorD
Engine coolant temperature sensorE- Vehicle speed sensor (reed switch)P
Evaporative emission purge solenoidHVolume air flow sensor (incorporating intake
Fuel pump check terminalTair temperature sensor and barometric pres-B
-sure sensor)
Idle speed control motor (closed throttle posi-
tion switch, idle speed control motor position
Csensor)
NOTEThe “Name” column is arranged in alphabetical order
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13-50 FUEL SYSTEM - On-Vehicule Inspection of MFI Components
INSPECTION
Using Scan Tool
Item No. Data display Inspection conditions
12Sensor de-
tection air
volume (fre-
quency) . Engine coolant
temperature: 85-95°C(185-205°F). Lights, cooling fan, elec-
trical accessories: OFF
. Transaxle: neutral (iVT
models: “P” range)
RacingFrequency in-
creases 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].
Regular waveform 03A0203
HARNESS INSPECTION
@
Harness sideconnector
6
0-0
~
0
=
Using Oscilloscope
(1) Run the engine at idle speed.
(2) Connect the probe to the
osilloscope pick-up point a
s
shown in the circuit diagram, and check the wave form.
Measure the power supply voltage.
. Connector: Disconnected
. Ignition switch: ON
--P
IRepair the
Harness sideconnector
Measure the terminal voltage.
. Connector: Disconnected
. Ignition switch: ON ~

0
OK’ 30
Repair the
harness
.
cm-an)
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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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