1991 MITSUBISHI 3000GT battery

FUEL SYSTEM - On-vehicle Inspection of MPI Components
IGNITION COIL AND POWER TRANSISTOR
MlBYVABEquipment side
connector@ Harness side
connector@ Harness side connector
Tachometer
-1Battery
/gnition coil1 3
Engine control unit
\/\/\IAL“8 “6.,,523No. 2No. 3
No 5No. 6
* transistor
5Y
lgnltlontamingadjust-
mentconnectof
11104
d
w5V
7FU1059Engine control unitconnector
7FUO453
OPERATION
lWhen the power transistor unit A is turned on by the signal from the engine control unit, primary current
flows to the ignition coil A. When the power transistor unit A is turned off, the primaty current is shut off
and a high voltage is induced in the secondary coil A, causing the ignition plugs of No. 1 and No. 4
cylinders to spark. When the
power transistor unit B is turned off, the ignition plugs of No. 2 and No. 3
cylinders spark.
L
lWhen the engine control unit turns off the transistor in the unit, the battery voltage in the unit is applied to
the power transistor unit to turn it on. When the engine control unit turns on the transistor in the unit, the
power transistor unit is turned off.
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FUEL SYSTEM - On-vehicle Inspection of MPI Components13-119PURGE CONTROL SOLENOID VALVE
Q Harness side
connector
I
Control relay
@ Equipment side
connector connector
unit
OlAO324
Engine control unit connector
7FUO653OPERATION
lThe purge control solenoid valve is an ON-OFF type one which controls introduction of purge air from the
canister into the intake air plenum.
lThe battery power is supplied to the purge control solenoid valve through the control relay. When the
engine control unit turns ON the power transistor in the unit, current flows to the coil, introducing purge
air.
INSPECTION
Using Multi-use Tester
Function
Actuator testItem No.Drive content
Check conditionNormal state
08Solenoid valve from OFFIgnition switch: ONOperating sound is heard
to ONwhen driven
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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.
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FUEL SYSTEM - On-vehicle Inspection of MPI ComDonents13-123FUEL PRESSURE CONTROL VALVE
Control relay
Fuel pressure
control valveEquipment
connectorside
Enaine control unit
connector
7FUO653
OPERATION
lThe fuel pressure control valve is an ON-OFF type solenoid valve that switches the pressure introduced to
the fuel pressure regulator between either intake manifold pressure or barometric pressure.
lBattery power is supplied to this valve via the control relay. When the engine control unit turns ON the
internal power transistor, the coil is energized to allow barometric pressure to be introduced to the fuel
pressure regulator.
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FUEL SYSTEM - On-vehicle Inspection of MPI Components13-125
ACTUATOR INSPECTION
Operation Check
NOTEBefore disconnecting the vacuum hose, mark it to ensure
reconnection at the correct position.
(1) Remove the vacuum hose (blue stripe on black) from the
solenoid valve.
(2) Disconnect the harness connector.
(3) Apply a negative pressure to the nipple to which the black
vacuum hose has been connected and check air-tightness
with and without the battery voltage applied to the solenoid
valve terminal.
BatteryvoltageThe other nipple
of solenoid valveNormal state
Not applied
qj
I
AppliedOpenNegative pressure isheld
Coil Resistance Check
(I) Measure the coil resistance with a circuit tester.
Standard value: 36
- 46 R [at 20°C (68”F)]
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13-126FUEL SYSTEM - On-vehicle Inspection of MPI Components
WASTE GATE CONTROL SOLENOID VALVE

7FU1007Control relav
Waste gate control
solenoid valve
Q Equipment side
connector
unit
0110324Enqlne control unit connector
7FUO653
OPERATIONlThe waste gate control solenoid valve is an ON-OFF type solenoid valve that controls the boost pressure
that is introduced to the waste gate actuator.
lBattery power is supplied to this valve via the control relay. When the engine control unit turns ON the
internal power transistor, the coil is energized to release part of the boost pressure applied to the waste
gate actuator.
TROUBLESHOOTING HINTSIf the waste gate control solenoid valve harness and the unit itself are normal, but poor acceleration or other
abnormalities are experienced, the
follwing problems are suspected.
(1) Faulty boost pressure control system
(2) Poor connection of intake air hose
(3) Faulty turbocharger or waste gate actuator
(4) Clogged exhaust system
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FUEL SYSTEM - Orwehicle lnwection of MPI Components.13-137Fuel gauge cover
03FOOO4
j check terminal ----T( 04~oo1,/RELEASE OF RESIDUAL PRESSURE FROM HIGH
PRESSURE FUEL HOSEM13FGAIMake the following operations to release the pressure remain-
ing in fuel pipe line so that fuel will not flow out.
(I) Remove the fuel gauge cover in the luggage compartment.
(2) Disconnect the fuel pump harness connector.
(3) Start the engine and after it stops by itself, turn the ignition
switch to OFF.
(4) Connect the fuel pump harness connector.
(5) Apply the specified sealant to the rear floor pan.
Specified sealant: 3M ATD Part No. 8509 or equivalent
(6) Install the fuel gauge cover.
FUEL PUMP OPERATION CHECK
M13FDAI
(1) Set the ignition switch at OFF.
(2) Check that when the battery voltage is directly applied to
the fuel pump check terminal (black), the operating sound
of the pump can be heard.
NOTESince the fuel pump is installed in the fuel
.tank, its
operating sound cannot be readily heard. Remove the fuel
tank cap and listen to the operating sound through the filter
port.
(3) Hold the high pressure fuel hose between your fingers and
check that the fuel pressure can be felt.
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13438FUEL SYSTEM - On-vehicle Inspection of MPI ComponentsI/
FUEL PRESSURE TESTMlJFNAT(1) Reduce the internal pressure of the fuel pipes and hoses.
(2) Disconnect the fuel high pressure hose at the delivery pipe
side.
dl
Caution
Cover the hose connection with rags to prevent splash
of fuel that could be caused by some residual pressurein the fuel pipe line.
(3) Set a fuel pressure gauge on the special tool, placing an
adequate O-ring or gasket between the gauge end special
tool prevent fuel leaks.
(4) Attach the special tool set in step (3) to the delivery pipe
between high pressure hose.
(5) Connect the 0 battery terminal.
(6) Connect a jumper wire to the terminal for activation of the
fuel pump and to the positive
0 terminal of the battery to
activate the fuel pump. With fuel pressure applied, check to
be sure that there is no fuel leakage from the fuel pressure
gauge and the special tool connection part.
(7) Disconnect the jumper wire (from the terminal for activation
’of the fuel pump) to stop the fuel pump.
(8) Start the engine and let it idle.
d(9) Measure the fuel pressure during idling.
Standard value:
Approx. 270 kPa (38 psi) at curb idle
Approx. 235 kPa (34 psi) at curb idle
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