fuel type MITSUBISHI 3000GT 1993 2.G Workshop Manual

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SERVICE SPECIFICATIONS
Items
Standard values
Speedometer indicationerror
mph
2019-22
4038-44
1 57-66
1 76-88I
1001 94-110I
Tachometerindicationerrorrpm1,000f 100
3,000
f150
5,000f 250
6,000
Ik 300
Fuel gauge unit resistance R/ Point F_I3f2I
Point E
Fuel gauge unit float heightPoint F
mm (in.)
Point E
Engine coolant temperature gauge unit resistance [at 70°C (158”F)] Q110+7
18.6-21.6 (.73-.85)193.4-l
96.4 (7.61-7.73)
104 f 13.5
Fuel gauge resistance QBetween A - B/ Approx. 254I
Between A - CApprox. 101I
Between B - CApprox. 153I
Enginecoolant temperature Between A - B
gauge resistance QBetween A - CApprox. 51
Approx. 139
Between B
- C/ Approx. 190I
Oil pressure gauge resistance QApprox. 42I
Pressure gauge resistance <Turbo> QApprox. 72ISEALANT
ItemsSpecified sealantType
Engine coolant temperature gauge3M Nut Locking Part No. 4171 or Semi-drying sealant
unitequivalent
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OPERATION
<Fuel gauge>l
When the ignition key is at the “ON” position,the fuel gauge is activated.
l
When there is much fuel, the unit’s resistanceis small and the current flowing in the circuit
is great, so the gauge’s indicator indicates inthe “F” area.
l When there is little fuel, the unit’s resistance
is high and the current flowing in the circuit
is small, so the gauge’s indicator indicates inthe
“E” area.
<Engine coolant temperature gauge>
lWhen the ignition key is at the “ON” position,
the engine coolant temperature gauge is acti-
vated.l
When the engine coolant temperature is high,
the unit’s resistance is low and there is a greatflow of current in the circuit, so the gauge’s
indicator indicates in the “H” area.
l
When the engine coolant temperature is low,
the unit’s resistance is high and there is a smallflow of current in the circuit, so the gauge’s
indicator indicates in the “C” area.
<Reed switch (mechanical speedometer type)
/Speed sensor (electrical speedometer type)>l Pulses are produced in accordance with the
vehicle speed, and vehicle-speed signals areinput to systems (the MFI system, etc.) that
regulate according to the vehicle speed.
TROUBLESHOOTING HINTS
1.The fuel gauge doesn’t function, or shows the
incorrect indication.
(1) Disconnect the connector of the fuel pumpand gauge unit assembly; the ‘F” side is
indicated when terminal (5) is then
grounded.l Check the fuel gauge.
2.The engine coolant temperature gauge doesn’t
function, or shows the incorrect indication.
(1)The “l-l” side is indicated when the connector
of the engine coolant temperature gauge
unit is disconnected and then grounded.l
Check the engine coolant temperature
gauge unit.
3. Systems dependent upon control according to
the vehicle speed do not function correctly.l Check the reed switch (mechanical
speedometer type)l Check the speed sensor (electrical
speedometer type)
coil pressure gauge>l
When the ignition key is at the “ON” position,
the oil pressure gauge is activated.
lWhen oil pressure is high, the internal contacts
of the gauge unit are kept closed for a longerperiod of time. This causes more current to
flow in the circuit, and the gauge pointer swings
to the high pressure side.
lWhen oil pressure is low, the internal contactsof the gauge unit open in a shorter period of
time. Therefore, there is less current flowing
in the circuit and the gauge pointer swings to
the low pressure side.
<Pressure gauge (TURBO)>
lWhen the ignition key is set to the “ON” position,the gauge indicator will be at
“0”.l
When the engine is started, the indicator will
move from
“0” to the minus (-) side, and then,as the boost level increases, it will move to
the plus
(+) side.
<Voltage gauge (NON-TURBO)>l When the ignition key is placed in the “ON”
position, the voltage gauge operates and indi-
cates a battery voltage of approximately 12 V.l
When the engine is started, the voltage gauge
indicates a battery voltage of 12 to 16 V, indicat-ing that the battery is on charge.
4. The oil pressure gauge doesn’t function, or
shows the incorrect indication.
(1)The “H” side is indicated when the connectorof the oil pressure gauge unit is discon-
nected and then grounded.l Check the oil pressure gauge unit.
5.The meter illumination light does not illuminate.
(1) The tail lights illuminate.l Check the rheostat.
6. The voltage gauge doesn’t function, or shows
the incorrect indication.l Check the voltage gauge.
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- Meters and Gauges54-27
c I\\ zl6F024;
L:FUEL GAUGE SIMPLE CHECKTACHOMETER CHECK
(1)insert paper clip into the engine revolution speed detection
terminal provided in the engine compartment, and connectthe engine tachometer to the inserted paper clip.
Caution
As the tachometer is negative grounded, do not con-
nect battery conversely to prevent damaging transis-tor and diode.
NOTE
For tachometer inspection, use of a fluxmeter-type engine
tachometer is recommended. (Because a fluxmeter onlyneeds to be clipped to the high tension cable.)
(2) Connect the engine tachometer and compare the engine
tachometer and tachometer readings. Replace tachometer
if difference is excessive.
Standard value:1,000
f 100 rpm
3,000
+ 150 rpm
5,000
f 250 rpm
6,000
f 300 rpm
CautionThe engine speed signal output from the engine is
one-third of the actual speed. When the engine speed
is measured, make sure that the engine tachometeris placed in the
2-cylinder range. (The real speed is
indicated.)
Connect a test light to the harness con-nector.
Place the ignition switch in the ON posi-
tion.Check the test light and gauge conditions.
1 (1) Test light lights. (Pointer of gauge does not swing.)/-.-I Replace fuel gauge.
[ (2) Test light lights. (Pointer of gauge swings.)/-.--I Replace fuel gauge unit.1
1 (3) Test light does not light. (Pointer of gauge does not swing.)k-1 Correct harness.I
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DISASSEMBLY AND REASSEMBLY
Disassembly steps
1. Trip counter reset knob
2. Meter glass
3. Window plate
4. Speedometer
Ground
Reed switch
16R027300002385
3
5. Fuel gauge6. Tachometer7. Printed-circuit board8. Meter case
INSPECTION
REED SWITCH CHECK
<Mechanical Speedometer Type>
Use circuit tester to check circuit repeats off/on between termi-\
nals when speedometer shaft turned several times.d
VEHICLES SPEED SENSOR CHECK
<Electrical Speedometer Type>
(1)Remove the vehicles speed sensor and connect as shownin the illustration, using a
3-10 k&2 resistance.
(2) Use a voltmeter to check for voltage at terminals (2) and
(3) when the pulse generator shaft is turning. (One revolu-
tion is four pulses.)
FUEL GAUGE CHECK
Measure resistance between terminals with circuit tester.
Standard value:
;I;Approx. 254 0Approx. 101
I2B-C
Approx. 153
fi
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