1991 MITSUBISHI 3000GT service

13-40FUEL SYSTEM -On-vehicle Inspection of MPI Components
COMPONENTS INSPECTION PROCEDUREM13YBAC
USING MULTI-USE TESTER
(1) Check by the service data and actuator test function. If any ij
abnormality is found, check the body harness, components,
etc. and repair as necessary.
(2) After repair, check again with the multi-use tester to makesure that the input and output signals are now normal.
(3) Erase the self-diagnosis trouble code in memory.
(4) Disconnect the multi-use tester.
(5) Start the engine and perform running test, etc. to make
sure that the troubles have been corrected.
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FUEL SYSTEM- On-vehicle Inspection of MPI Components13-81
INSPECTIONUsing Multi-use Tester
Function
Data readingItem No. Data displayCheck conditionSteering wheelNormal indication
27Switch stateEngine: IdlingSteering wheel neutralOFFposition (wheels
straight-ahead direction)
Steering wheel half turn
ON
Checking Oil Pressure
Steering wheelOil pump delivery pressure (ref. value)
Straight forward700 - 1,200 kPa (100 - 171 psi)
Turned1,500
- 2,000 kPa (213 - 284 psi)
HARNESS INSPECTION
i1
@ Harness side
connector
Measure the power supply voltage.
SENSOR INSPECTIONRefer to GROUP 37
- Service Adjustment Procedures.
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FUEL SYSTEM - On-vehicle Inspection of MPI Components
AIR CONDITIONER POWER RELAY
L
FunctionItem No. Data display
Data reading49Air condi-tioner relay
stateCheck conditionEngine: Idling after
warm-up
HARNESS INSPECTIONAir conditioner switch
Normal indication
OFFOFF (compressor
clutch non-activa-
tion)
ONON (compressorclutch activation)
’ I
unit harness
side connector
7FUO695
Measure the power supply voltage of
the air conditioner circuit.l
Air conditioner switch: ONlEngine control unit connector:
Disconnectedl Ignition switch: ON
l
Dual air conditioner switch: ONVoltage
(V)IM
ASTOP
Check the airconditioner
circuit.
AIR CONDITIONER INSPECTIONRefer to GROUP 55
- Service Adjustment Procedures.
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FUEL SYSTEM - Injector13-141
INJECTOR
LREMOVAL AND INSTALLATION
!
MlBSA-A
/
LPre-removal Operation
l Draining of the Coolant
(Refer to GROUP 00
- Maintenance Service.)
l Removal of Air Intake Plenum
(Refer to GROUP
15-Air Intake Plenum,)
l Release of Residual Pressure from High
Pressure Hose.
(Refer to P.13-137.)
5Nm
4
WbsPost-installation Operation
l Supplying of Coolant
(Refer to GROUP 00- Maintenance Service.)
l Installation of Air intake Plenum
(Refer to GROUP 15 -Air Intake Plenum.)
l Checking for Fuel Leakage
03FOO17
Removal steps
l * l *1. Connection of high pressure fuel hose
2. Connection of fuel return hose
3. Connection of vacuum hose
l *4. Fuel pressure regulator
5. Connection of control harness
6. Fuel pipe
7. Delivery pipe8. Insulator
9. Injector support*+ IO. Injector11. Insulator12. O-ring13. Grommet
:m
*:”
-aI : %~’.1X.-10p$
y&,*,,A200A0005
0-hng4O-ring
03N001203FOO18
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13-142FUEL SYSTEM - Injector
SERVICE POINT OF REMOVAL
MlBSSAI1. DISCONNECTION OF HIGH PRESSURE FUEL HOSE
Bleed the residual pressure within the fuel pipe line so as to
LA;prevent the flow of fuel.
Caution
Cover the hose connection with rags to prevent splash
of fuel that could be caused by some residual pressurein the fuel pipe line.
INSPECTION
INJECTORS
M13SCAC(1) Measure resistance between terminals of injector using a
circuit tester.
Standard value:13
- 16 R [at 20°C (68”F)]
2
- 3 LR [at 20°C (68”F)l
(2) If the resistance is out of specification, replace the injector.
SERVICE POINTS OF INSTALLATION
MlBSDAV
10. INSTALLATION OF INJECTORWhile turning the injector to the left and right, install it to the
delivery pipe.
Check to be sure that the injector turns smoothly.
LCaution
If it does not turn smoothly, the O-ring may be trapped.Remove the injector and then
m-insert it into the
delivery pipe and check once again.
4. INSTALLATION OF FUEL PRESSURE REGULATORWhen connecting the fuel pressure regulator to the delivery
pipe, apply light oil or petrol to the O-ring, and then insert,
being careful not to damage the O-ring.
1. CONNECTION OF HIGH PRESSURE FUEL HOSE
When connecting the high pressure fuel hose to the
delivery pipe, apply petrol to the hose union, and then
insert, being careful not to damage the O-ring.
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FUEL SYSTEM - Throttle Body13-143Pre-removal and Post-installation Operation
l Draining and Supplying of Engine Coolant
(Refer to GROUP 00 -Maintenance Service.) - California>
3
THROTTLE BODY
I
idREMOVAL AND INSTALLATION
MIOSA-0
3\
OlFOOO4
NOTEThe layout of vacuum hoses (No. 3) of the constris for the DOHC (Non Turbo) - Federal.
OlFOO53
I drawing
Removal sl
+*1.Connection of accelerator cable2.Connection of air intake hose3. Connection of vacuum hose
4. Connection of TPS connector
5. Connection of
ISC motor connec6. Connedion of water hose
7. Vacuum pipe assembly
8.ThrottlebodyI)*9.Gasket
:eps
:tor
PrelectionThrottle bodySERVICE POINTS OF INSTALLATIONMlBSDAW9. INSTALLATION OF GASKET
Install the gasket so that the projection is where shown in
the illustration.
CautionPoor idling etc. may result if the gasket is installed
incorrectly.
1. ACCELERATOR CABLE ADJUSTMENTFor information concerning adjustment of the accelerator
cable, refer to
P.13-156.
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13-144FUEL SYSTEM - Throttle- Body
DISASSEMBLY AND REASSEMBLY
2.0
Nni1.4ft.lbs.
/
Disassembly steps
1. Dash pot2. Hose
3. Vacuum valve
>

l *4. Throttle position sensor
(within idle position switch)
5.
Idle speed control servo
assembly
6. Throttle body
7FU1023
\7FU1057 1SERVICE POINT OF DISASSEMBLY
MlBSFAN
Caution
1.When loosening a Phillips screw which has been firmly
tightened, use a Phillips screwdriver that is an exact fitfor the screw.
2. Do not remove the throttle valve.
3.Be careful when removing the throttle position sensorand idle speed control servo mounting screws, as
adhesive has been applied these screws.
INSPECTION
Ml3SHAt.lDASH POT INSPECTION
(1) Check the dash pot diaphragm for damage. First, push up
the rod fully and closing tightly the nipple with a finger,
release the rod. The diaphragm is intact if the rod does not
return to the initial position while the nipple is held closed
with a finger. If the rod returns, the diaphragm is broken.
Replace the dash pot.
VACUUM VALVE INSPECTION
(1) Remove the filter from the vacuum valve.
(2) Connect a hand vacuum pump to the black nipple of the
vacuum valve.
(3) With the other nipple closed by the finger, apply a negative
pressure of 500 mmHg (19.7 in.Hg.) to make sure that the
negative pressure is maintained.
(4)Let go your finger and make sure that the negative pressure
leaks out gradually.
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FUEL SYSTEM - Throttle Body13-145Orifice
Nipple (green)3EM05iGroundThrottle
positlonsensor output
Idle-position
switchTh>ottle position
sensor power7FUO535(5) Disconnect the hand vacuum pump and connect it to the
other nipple.
(6)Make sure that the negative pressure leaks out as soon as it
is applied.
CLEANING THROTTLE BODY PARTS
(1) Clean all throttle body parts.
Do not use solvent to clean the following parts:
l Throttle position sensor (Idle position switch)
l Idle speed control servo
If these parts are immersed in solvent, their insulation will
deteriorate.
Wipe them with cloth only.
(2) Check if the vacuum
pot-t or passage is clogged. usecompressed air to clean the vacuum passage.
SERVICE POINT OF REASSEMBLY
M13SGAN4. INSTALLATION OF THROTTLE POSITION SENSOR
(1) Set the throttle position sensor to the throttle body as
shown in the diagram.
(2) After turning the throttle position sensor 90” in the
clockwise direction to set it, tighten by turning the
screw.
(3) Connect the circuit tester between 1 (ground) and 3
(output), or between 3 (output) and 4 (power). Then,
make sure that the resistance changes smoothly when
the throttle valve is slowly moved to the fully open
position.
(4) Check for continuity across terminals 2 (Idle position
switch) and 1 (ground) with the throttle valve both fully
closed and fully open.
IThrottle valve positionIContinuityI
Fully closedConductive
Fully openINon-conductiveIIf there is not continuity with the throttle valve fully
closed, turn the counterclockwise direction, and then
check again.
(5) If the above specifications are not met, replace the idle
position switch.
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