1991 MITSUBISHI 3000GT lock

FUEL SYSTEM - Service Adjustment Procedures13-35
ADJUSTMENT OF FIXED SASMlJFlDC
NOTE
(1) The fixed SAS has been factory-adjusted. Never attempt tomove it.
(2) Should it be out of proper adjustment, adjust by following
the procedure given below.(I) Sufficiently slacken the accelerator cable.
(2) Loosen the lock nut on the fixed SAS.
(3) Sufficiently loosen the fixed SAS by turning it counterclock-wise to fully close the throttle valve.
(4) Tighten the fixed SAS slowly to find a point at which it
contacts the throttle lever (where the throttle valve starts
opening). From that point, tighten the fixed SAS further 1 l/4
turns.
(5) Holding the fixed SAS to prevent it from turning, tighten thelock nut securely.
(6) Adjust the accelerator cable tension. (Refer to
P.13-156.)(7) Adjust the basic idle speed. (Refer to
P.13-31.)
(8) Adjust the idle position switch and throttle position sensor
(TPS). (Refer to P.13-33.)
1 TSB Revision

13-64FUEL SYSTEM - 0
n-vehicle Inspection of MPI Components
7FUO670
Apply sealant
7FUO67’SENSOR INSPECTION
(1) Remove engine coolant temperature sensor from the
intake manifold.(2) With temperature sensing portion of engine coolant
temperature sensor immersed in hot water, check resis-
tance.
Temperature
“C (“F)Resistance (kCI)
0 (32)5.8
20 (68)2.4
40 (104)1.1
80 (176)0.3
(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: 30 Nm (22
ft.lbs.)
(3) Fasten harness connectors securely.TSB Revision

FUEL SYSTEM - On-vehicle InsDection of MPI ComDonents13-69
HARNESS INSPECTION
arness sideconnector
7FUO675
Measure the power supply voltage of
the idle position switch.
l Connector: Disconnectedl Ignition switch: ON
Check for continuity of the groundcircuit.
l Connector: Disconnected
SENSOR INSPECTION
sensor tonne
ASTOP
Repair the
harness.
@w--~)
(1) With the accelerator pedal released, check to be sure thatthe throttle valve lever or the fixed SAS is pushed.
NOTE
If it is not pushed, adjust the fixed SAS (Refer to P.13-35.)(2) Disconnect the throttle position sensor connector.
(3) Check the continuity across the throttle position sensor
connector terminal @ (Sensor ground) and @ (Idle position
switch).
Accelerator pedal
Depressed
Released
Continuity
Non-conductive
(a~ KU
Conductive (0 fi)
7FUO676
NOTE
If there is no continuity when the accelerator pedal is returned,loosen the throttle-position sensor installation screw; then,
after turning all the way in the counterclockwise direction,
check again.
(4) Replace the throttle-position sensor (idling-position switchincorporated) if there is a malfunction.
NOTEFor the idle position switch and throttle position sensor
adjusting procedure, refer to
P.13-33.TSB Revision

13-82FUEL SYSTEM - On-vehicle Inspection of MPI Components
AIR CONDITIONER SWITCH AND POWER RELAY
\
*I \\-- \
Air conditronerAir conditioner
control unitAir conditioner
compressor lock
controllerr
Engine control unit
Dual pressureswitch
M13YRAA2
b1IFF
Air conditioner
compressor
Engine control
unit connector
7FUO966
7FUO653
OPERATION
lThe air conditioner switch applies the battery voltage to the engine control unit when the air conditioner is
turned on.
lWhen the air conditioner ON signal is input, the engine control unit drives the idle speed control servo and
turns ON the power transistor. As a result, the air conditioner power relay coil is energized to turn on therelay switch, which activates the air compressor magnetic clutch.
TROUBLESHOOTING HINTS
If the air compressor magnet clutch is not activated when the air conditioner switch is turned on during idling,faulty air conditioner control system is suspected.
INSPECTION
Using Multi-use Tester
AIR CONDITIONER SWITCH
Function1 Item No. 1 Data display 1Check condition) Air conditioner switch 1 Normal indication IData reading 28
Switch stateEngine: Idling (airOFFOFFcompressor to be running
when air conditionerONONswitch is ON)\k”JTSB Revision

13-84FUEL SYSTEM - 0n-vehicle Inspection of MPI Components
DETONATION SENSOR
Engine control unitN
/J-l
@ Equipment side58: :connectorI I
t- =I IL .J531 5:2::
i SEL1208j
@ Harness side
connector7FU1075
Engine control unit connector
7FUO653
OPERATION
The detonation sensor generates a voltage proportional to the magnitude of cylinder block vibration due to
knocking and inputs it to the engine control unit. Based on this signal, the engine control unit provides retardcontrol of the ignition timing.
TROUBLESHOOTING HINTS
When knocking occurs while driving under high-load conditions, the following problems are suspected inaddition to the detonation sensor itself.
(1) Inappropriate ignition plug heat range
(2) Inappropriate gasoline(3) Incorrectly adjusted reference ignition timing
TSB Revision

FUEL SYSTEM - On-vehicle lnwection of MPI ComDonents13-121
LEGR CONTROL SOLENOID VALVE - Non Turbo, Turbo>MlBYZBAControl relav
EGR control
solenoid valve@ Equipment side
connector
Engine
control
unitEngine control unit connector
7FUO653
OPERATION
lThe EGR control solenoid valve is a duty control type solenoid valve. It makes control by leaking EGR valve
operating negative pressure to the throttle body A port.
lPower supply from the battery is sent through the control relay to the EGR control solenoid valve. When
the engine control unit turns off the power transistor inside the unit, current no more flows through the
coil and EGR valve operating negative pressure leaks.
TROUBLESHOOTING HINTIf the results of EGR control solenoid valve on-vehicle and off-vehicle inspections are normal but the
self-diagnosis code for EGR system failure is displayed, check the EGR valve, vacuum hose and EGR passage
for blocking.
c.
1 TSB Revision

FUEL SYSTEM - On-vehicle lnwection of MPI ComDonents13-131
iVARIABLE INDUCTION CONTROL SERVO (DC MOTOR) Variable induction control servo
Y(DC motor)(with built-in induction/-control valve oosition sensor)-7Fllfl807Engine control unit
Close
connector
,\ IOpen@ Equipmentside1,,I2DC motorVariable
induction
control
servo
1 FU0646
Engine control unit connector
7FUO653
OPERATION
lAs the DC motor is driven clockwise or counterclockwise by the signal from the engine control unit, the
variable induction valve opens or closes.
lThe DC motor is driven clockwise or counterclockwise as the direction of current flow is changed by the
motor drive
IC in the engine control unit.
INSPECTIONUsing Multi-use tester
Function
Actuator testItem No.Drive content
Check conditionNormal state
11Drive the variable induc-Ignition switch: ONTurn the variable inductiontion control (MC) servovalve shaft (Variable induc-
(Open and close the
vari-tion valve: FULL CLOSEable induction valve)+ FULL OPEN
1 TSB RevisionI

FUEL SYSTEM - On-vehicle Inspection of MPI Components
ANTI-LOCK BRAKE SIGNAL
Engine control
unit connectorABS ECU@ ABS control unit
equipment side connector
A28
tABS HU
Engine
control
unit
114
/L6FU1542
7FUO653,
OPERATIONlThe anti-lock brake signal is input to the engine control unit from the anti-lock brake system
(ABS) control
unit as a signal to indicate whether or not the motor relay is activated. Based on this signal, the engine
control unit controls the idle-speed control servo to secure effective anti-lock braking.
lWhen the motor relay is activated, the ABS control unit turns ON the power transistor, short-circuiting the
terminal to ground. This causes the anti-lock brake signal to go from high to low.
TSB Revision