1991 MITSUBISHI 3000GT check engine

23-38AUTOMATIC TRANSAXLE - Troubleshooting
12. Kickdown
(K/D) servo
switch
19=111
TFAO389
Check for continuity between thePoor contact, or dam-
kickdown servo switch terminalaged or disconnected
and the transaxle case.wiring
+c
Continuity existsReplace the K/D servo
+switch.
Start the engine, set to the “L”range, and let the engine idle;check for continuity between thekickdown servo switch terminalPoor contact (sticking)
and the transaxle case.
NOTE: Be sure the brakes are
applied during this check.4
+Replace the K/D servo
No continuityswitch.
+I
NormalIr
Disconnect the harness (both A
13. Transaxle con-and B connectors) from the vehi-
trol unit(TCU)cle’s TCU. Then connect, via an
intermediate harness for check-
ing, a new TCU to this harness
and make a road test.4
Install a new TCU.
Consider the original TCU to be
normal, and again check the sen-sors. wiring, etc.
4
Same problem (as before TCU
exchange) occurs.
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AUTOMATIC TRANSAXLE - Troubleshooting23-39
//!’ 6Rear@FrontclutchpressureI
@Kickdown brakeoressure (Release)
e
OIL PRESSURE TESTS1. Completely warm up the transaxle.
2.Raise the vehicle by using a jack so that the front wheels
can be rotated.
3. Connect an engine tachometer and place it in a position
where it’s easy to see.
4. Attach the special oil-pressure gauge (MD998330-01) and
the adaptor (MD998332-01) to each oil-pressure outlet port.
When the reverse pressure is to be tested, the 3,000
kPa(400 psi) type of gauge should be used.
5. Measure the oil pressure under various conditions, and
check to be sure that the measured results are within the
standard value range shown in the “Standard oil pressure
table” below.
If the oil pressure is not within the specified range, check
and repair as described in the section “Remedial steps if oil
pressure is not normal” on the next page.
STANDARD OIL PRESSURE TABLECondtttonsStandard
011 pressurekPa (PSI)No
SelectEngme
Red&g@000E%00leverspeedGearK/D brakeWD brakeFrontRearLow-TorqueposItlollvposltlon
pressurepressurepressureclutchclutchclutchreverseconverter
(application)(release)
pressurepressurepressurebrakepressure
pressure
1Nldlmg
Neutral
360 - 4808,(51 - 6812
Dldlmg
2nd
360
- 480100-210
730 -830k(51 - 68)
(14-30)
(104 -118)
3(SWFON,
Approx.
4th
360 480
830
-900
830
900
450-650
2,500(51 - 68) (118 128)(118 128)(64 92)
(SWZFF)Approx.
3rd
360 - 480
830
900830 -900 830 - 900
830 -900830
900
450-4
650-2.500(51 - 68)
(118
128)(118 -128) (118 - 128)
(118
128)(118128)
(64-921
52
Approx.
2nd
360
- 480
830--900
830 -900
450
650
2,500
(51 - 68)
(118-128)
(118 -128)
(64-921
Approx
1 st360 480
830 -900
300-450A1.000(51 - 68)
(118 -128)I43 .-64)
Approx.
Reverse
360 480
1.6402.2401.640 2.2401.640 -2.240450-6502.500(51 - 68)(233 - 319) (233 319)(233 319)(64 ~- 921
Approx.
Reverse
360
- 4801.500(213) 1.500 (213)1.500(213)
450~-650
1,000(51 - 68)or moreor moreor more(64 - 92)NOTE
(I)
-: Indicates pressure is below 10 kPa (1.4 psi).
(2)SW-ON: OD switch in ON position.
(3)SW-OFF: OD switch in OFF position.
(4)
a: Pressure IS not standard.
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AUTOMATIC TRANSAXLE - Troubleshootinn23-43
CONVERTER STALL TESTStall test consist of determining maximum engine
speed obtained at full throttle in “D” and
“I?”positions. This test checks torque converter
statoroverrunning clutch operation, and holding ability of
transaxle clutches and low-reverse brake.
Caution
During this test, make sure that no one stand in
front of or behind vehicle.
1. Check transaxle fluid level. Fluid should be at
normal operating temperature
[70 - 80°C (160 -
18O”F)I. Engine coolant should also be at normal
operating temperature
[80 - 90°C (180 - 19O”F)l.2. Apply chocks to both rear wheels.
3. Attach engine tachometer.
4. Apply parking and service brakes fully.
5. Start engine.
6. With selector lever in “D” position, depress
accelerator pedal fully to read engine maximum
rpm. Do not hold throttle wide open any longer
than is necessary to obtain maximum engine
rpm reading, and never longer than 5 seconds at
a time. If more than one stall test is required,
operate engine at approximately 1,000 rpm in
neutral for 2 minutes to cool transaxle fluid
between tests.
Stall speed: 2,200
- 3,200 rpm
7.Place selector lever to “R” position and perform
stall test by the same procedure as in foregoing
item.
Stall Speed Above Specification in “D”
If stall speed is higher than specification, rear clutch
or overrunning clutch of transaxle is slipping. In this
case, perform hydraulic test to locate cause of
slippage.
Stall Speed Above Specification in “R”
If stall speed is higher than specification, front
clutch of transaxle or low-reverse brake is slipping.
In this case, perform hydraulic test to locate cause
of slippage.
Stall Speed Below Specification in “D” and “R”
If stall speed is lower than specification, insufficient
engine output or faulty torque converter is sus-
pected. Check for engine misfiring, ignition timing,
valve clearance, etc. If these are good, torque
converter is faulty.
TRANSAXLE CONTROL
Symptom
Selector lever operationis stiff
Probable cause
Incorrect adjustment of sleeve
Remedy
Adjust
Incorrect adjustment of control cable
Excessive wear of detent plate
Worn contact surfaces of pushbutton
and sleeve
Adjust
Replace
Replace
Starter motor does notMalfunction in inhibitor switchReplace
operate with the selector
lever in the “N” or “P”Incorrect adjustment of control cableAdjust
position
Will not shift to
4-speed
Malfunction of starter relay
Malfunction of OD switchReplace
Replace
1 TSB RevisionI

23-50AUTOMATIC TRANSAXLE - service AdiustmentProcedures
09FO117
m09FOO19
L Pushbuttonv09FOO61
@ Button pressed (while brakepedal is depressed)c Button not pressed@ Button pressed
/\ \\ OSFODdACCELERATOR SWITCH INSPECTION AND
ADJUSTMENTM23FZAACheck that current flows between terminals of accelerator
switch when accelerator pedal is in free state and that no
dcurrent flows when the pedal is depressed and the specified
stroke A is obtained.
Standard value: 2
- 6 mm (.079 - .24 in.)
‘If stroke A is out of specification, adjust with adjusting bolt.
SELECTOR LEVER OPERATION CHECKM23FIAG
1.. Shift selector lever to each range and check that lever
moves smoothly and is controlled. Check that position
indicator is correct.
2.Check to be sure the selector lever can be shifted to each
position (by button operation as shown in the illustration).
3. Start the engine and check if the vehicle moves forward
dwhen the selector lever is shifted from N to
D, and moves
backward when shifted to R.
4.When the shift lever malfunctions, adjust control cable and
selector lever sleeve. Check for worn shift lever assembly
sliding parts.
I
NOTETo move the selector lever from the “P” position to any
other position, first turn the ignition key to any position
other than “LOCK” and depress the brake pedal.
KEY INTERLOCK MECHANISM CHECKM23FlJACCompletely stop the vehicle and switch OFF the engine before
making the check
1.Check to be sure that, under the following conditions, the
selector lever cannot be moved from the “P” position to
any other position.
Also check, at the same time, that the button cannot be
pressed.
Ignition key position: “LOCK” or removed
Brake pedal: Depressed
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POWER PLANT MOUNT - Engine Mounting
ENGINE MOUNTING
REMOVAL AND INSTALLATION
32-3
l Raise and Suspend the Engine to the12 Nm
lOO-120Nm(9 ftlbs.
72-87ftlbs. > &6
rI’ I/4
c*1. Connection for air hose G
2. Cruise control pump and link assembly

3. Engine mount bracket and body
connection bolt
4. Engine mount bracket
l *5. Mounting stopper
6. Dynamic damperOlFOO50
3emoval steps
SERVICE POINT OF REMOVALM32GBAK2. REMOVAL OF CRUISE CONTROL PUMP AND LINK
ASSEMBLY
Remove the actuator mounting nuts and place the actuatorwhere it will not interfere with the work.
INSPECTIONM32GCAMl
l Check each insulator for cracks or damage.
l Check each bracket for deformation or damage.
1SERVICE POINT OF INSTALLATIONM32GDAW
5. INSTALLATION OF MOUNTING STOPPER
Attach the engine mounting bracket so that the arrow mark
on the mounting stopper is in the direction as shown in the
illustration.TSB Revision

POWER PLANT MOUNT - Engine Roll Stopper
ENGINE ROLL STOPPER
REMOVAL ANDINSTALLATION
32-5
MJZGF- .
Pre-removal and Post-installationOperationl Removal and Installation of Condenser
Fan Motor Assembly
(Refer to GROUP 55 - Condenser and
Condenser Fan Motor.)
l Removal and installation of Catalytic
Converter (Left)
(Refer to GROUP 15 -Turbocharger.)
45 Nm/33 ft.lbs.
43
- 51 ftlbs.Front stopper bracket removal steps
1. Front roll stopper bracket and engine
connection bolt
2. Front roll stopper bracket installation bolt
3. Front roll stopper bracket
4. Heat protector

50-60 Nm36 - 43 ft.lbs.Rear roll stopper bracket removal steps
5. Air hose A
6. Air intake hose C
l +7. Rear roll stopper bracket and engine
connection bolt
8. Rear roll stopper bracket installation bolt
+* *+9. Rear roll stopper bracketIO. Heat protector OlFOO30
II\ OlFOO4:
SERVICE POINT OF REMOVALM32GEAL
9. REMOVAL OF REAR ROLL STOPPER BRACKET
(1) Slightly raise the rear roll stopper bracket.
(2) Turn the rear roll stopper bracket in the direction shownin the illustration and lift upward to remove.
INSPECTIONM32GCAM3l Check each insulator for cracks or damage.
l Check each bracket for deformation or damage.
9TSB Revision
SERVICE POINTS OF INSTALLATIONM32GJAC
9. INSTALLATION OF REAR ROLL STOPPER BRACKETInstall the rear roll stopper bracket as shown in the
illustration.7. INSTALLATION OF REAR ROLL STOPPER BRACKET
AND ENGINE CONNECTION BOLT
Install the bolt as shown in the illustration.

33B-4ELECTRONIC CONTROL SUSPENSION (ECS) - TroubleshootingTROUBLESHOOTING
M33EAAE
QUICK REFERENCE CHART FOR TROUBLESHOOTING
SymptomsXS
indicator lightdoes not switch
TROUBLESHOOTING HINTS
“1. The G. sensor is a sensor associated with ride control (detecting pitching, bouncing and rough road). If itfails, therefore, ride control stops.
“2. A self diagnostic decision on the steering angular velocity sensor is made by the ECS control unit which
internally detects the voltages of the two sensor output lines connected to the ECS control unit to detectan open circuit in the signal line. When the signal line is short-circuited or when the power line is
open-circuited, however, it cannot be detected. In a situation where anti-roll control only stops, if
self-diagnosis code No. 21 is not on display, a short-circuited sensor output line or open-circuited sensorpower line is suspected.
“3. The vehicle speed sensor is a sensor associated with attitude controls (anti-dive, anti-squat) and steering
stability controls (anti-roll, high speed sensitive controls). If all these controls stop, therefore, trouble in the
sensor is suspected. The vehicle speed sensor is also in use for operation of the speedometer and for theother electronics controlled systems for the engine, automatic transaxle, etc.
“4. The sensor associated with anti-squat control is the throttle position sensor. The sensor is also used for
control of the engine and automatic transaxle. If the sensor fails, therefore, the check engine light in the
combination meter will light, and engine self-diagnosis code No. 14 will be output. In a situation whereanti-squat control only stops, therefore, if the check engine light does not light, defective wiring is
suspected between the ECS control unit and throttle position sensor.
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ELECTRONIC CONTROL SUSPENSION (ECS) - Troubleshooting 33B-11
I I7
Anti-squat control only stops.III
L,
I
Using MUT, check service data onthrottle position sensor. Good?
Yes
rCheck by entering simulated vehicle speed from MUT to
simulate anti-squat control. (Refer to P.33B-16.) Good?!
1 Good1 ) Replace ECS control unit. 1
I
1I II
NoDoes check engine light illuminate?>Is continuity provided between No. 2 terminal of throttleposition sensor and No. 59 terminal of ECS controlunityII
Yes
i
Correct harness.
1Check throttle position sensor. (Refer to P.33B-20.) Good?III1
connector and check harness con-nector with ignition switch at ON.
No. 1 terminal voltage and continuityNo
Is
between No. 4 terminal and groundcontinuity provided across the following areas?
up to specification? (Sensor powerthrottle position sensor and engine control unit
No. 1 and 61 terminals
supply and ground)
No. 4 and 72 terminalsStandards:
INo. 1 terminal5 V
YesNo. 4 terminal
Continuity provided
Yes-1 1 Correct harnei:
”
Replace throttle position sensor.TSB Revision