1990 MITSUBISHI SPYDER check engine

ENGINE (NON-TURBO)>
INSPECTION PROCEDURE 44
Check the vehicle-speed sensor and speedometer.
Measure at the speed sensor connector l Disconnect the connector and measure at the harness side.
l Voltage between 1 and ground (Ignition switch: ON)
OK: 8.5-9.5
l Continuity between 2 and ground
OK: Continuity
OK
C h e c k t h e
Check the harness wire PCM and the speed connector. Repair, if necessary.
Check the followina connector: NG Repair
OK
Check trouble symptom.
NG
NG
Check the harness wire between the PCM and the spee d sensor Repairconnector.
SCAN TOOL SENSOR (Data list)65 Vehicle speed
l Is actual vehicle soeed indicated durina drivina?I
No
Check the speedometer circuit.
(Refer to INSPECTION PROCEDURE 45.)I
OK
Replace the vehicle speed sensor.
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SCAN TOOL SENSOR READ TESTS (Data list)
65 Vehicle speed
l
Is actual vehicle speed indicated during driving?
No
Yes Replace the PCM.
. . .
NG I):
Repair. .
. -
Check trouble symptom. , .
NGCheck the harness wire between the PCM and the tran saxle control Repairmodule connector.
OK
INSPECTIONPROCEDURE 45.)
OK
Check the automatic transaxle control system.

ENGINE (NON-TURBO)> Troubleshooting
INSPECTION PROCEDURE 45Check the speedometer.
A-l A-l 07,
OK
Check trouble symptom.
NG
Check the harness wire between the PCM and the comb ination
meter. Repair, if necessary.
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.

ENGINE (NON-TURBO)> Troubleshooting
SENSOR READ TESTS (DATA LIST) REFERENCE TABLE
Caution
1. When shifting the select lever to range, the brakes should be applied so that the
does not move forward.
2. When checking while driving the vehicle, always be sure to have two
vehicle.
Inspection
No.itemInspection contents
Normal conditionp r o c e d u r e
N o .
Engine: WarmWhen at 4000 Air/fuel mixture
engine is suddenly 200 or less
made leaner
decelerated.when
decelerating, and
sensor is made richer
When engine is 1,000
voltswhen racing.
suddenly raced.
(Heated
oxygenEngine: Warm
The heatedsensoroxygen sensor Engine: Idlefront)signal is used to
400 or less to
check the air/fuel
1,000
mixture ratio, and (Changes)
control condition is also checked Engine: 2000
by the PCM.
When engine coolant
t e m p e r a t u r e i s
When engine coolant
t e m p e r a t u r e i s
Engine
coolantIgnition switch: ON When engine coolant
or with engine run- temperature is
ture sensorning
When engine coolant
t e m p e r a t u r e i s
When engine coolant
t e m p e r a t u r e i s
Throttle Set to idle position.
400 or more
position Ignition switch: ON
Open fully 3,800
or less
Minimum
throttle Engine: Idle (more than one minute) 1,000
KnockCode
sor voltsEngine: Idle Sudden racingvoltage increases
temporarily.
0Battery
voltage Ignition switch: ON
101
1
Altitude: Om (0 ft.)
reading
Ignition switch: ON (30Altitude:
(3937 ft.)88 (26
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ENGINE (NON-TURBO)> Troubleshooting
,
p a g eNo.
66
39
71
inspection
No.
Procedure
Inspection
itemInspection contentsNormal condition
Engine: Warm
Air/fuel mixture
made leaner
whenWhen at 4,000
engine is suddenly
decelerated.L e a n
sensor
state
(Heated
oxygen
sensor
-front)
decelerating,and
is made richer When engine is
when racing. suddenly raced.
Engine: Warm
The heated
oxygensensorEngine: Idle
signal is used to
check the air/fuel
Rich
Lean Center
(Changes)mixture ratio. and
control condition is also checked Engine: 2,000
by the PCM.
MAPl
Engine: Warm, idleThe same
lUse a vacuum gauge to measure the indication as the
reading plenum vacuum.vacuum gauge Procedure
Procedure
Total spark
advance
Engine: Warm, idle
Approx.
sensor
state
(Heated
oxygen
sensor
rear)
l Transaxle: gear range l Drive with open throttle Engine: 3,500
or‘4more
Code No.
No.
or
Fuel level
sensor‘8
Fuel level
Fuel tank: Full
Fuel tank: Empty
‘9
Code
Long terml
Engine: Warm, 2,500 Increases
fuel trimDisconnect any injector connector. gradually
Engine: Warm, 2,500
Short termlDisconnect any injector connector. Increases and returns
fuel trimto the original
state.
Idle
Calculated
load valueEngine: Warm M/T
2,5006-12
9-14
General Scan Tool (GST) mode
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ENGINE
INPUT STATE TESTS (DATA LIST) REFERENCE TABLE
Item Inspection
No.itemInspection contentsN o r m a l c o n d i t i o n p r o c e d u r e
No.
A l
Power
steering
switch
switch
When steering wheel
is stationaryOFF
Engine: Warm, idle
When steering wheelONis turned,
Transaxle: or
rangeIgnition switch: ON
Other than
or range
BrakeDepress the brake pedalON
switch Do not depress the brake pedal.
(ASD)
voltage OFF
senseIgnition switch: ON
relay (ASD
C o d e N o .
relay)
erationON’checking Engine: Cranking or idle
voltage]
voltage Ignition switch: OFF
OFF
sense
(Ignition
switchSTART, ON voltage)Ignition switch: ON/START
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ENGINE (NON-TURBO)> , ,
OUTPUT STATE TESTS (DATA LIST) REFERENCE TABLE
Item Inspection
No. itemInspection contentsNormal condition ,
No.
TorqueWhen running at constant speed
reduction,
linkWhen shiftingUP, DOWN
A/C switch: OFFOFF
A/C clutch
relayEngine: IdleA/C switch: ON (A/C ON
compressor activated)
relayIgnition switch: ON
OFF
Engine: Cranking or idle
Engine: WarmRight after starting en-
gine
tive purge
solenoid
Engine: Warm1 0 s e c o n d s o r m o r e
after starting engine
Engine: Warm, idleON
E G R s o l e -OFFSlight racing (Engine: 2,000 or more)( m o m e n t a r i l y ). ..
Radiator fan: Not activated [Engine coolant
Radiator temperature: Less than approx. (176” F)]
fan lowRadiator operates at low speed [Engine coolantspeed relaye m p e r a t u r e i s or less, A/C ON
switch: ON]
Radiator fan: Not activated [Engine OFF
Radiatortemperature: Less than approx.
fan high
speed relay Radiator operates at high speed.
ngine coolant temperature is (220” F)ON
or more, A/C switch: ON]
Fuel pumpIgnition switch: ON
OFF
relayEngine: Cranking or idleON
(CheckIgnition switch: OFF ON
ON OFF
engine)(Everything is OK and DTC is not memorized) (Severa l minutes
lamp later)
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ENGINE (NON-TURBO)>
ON-VEHICLE SERVICE
THROTTLE BODY MINIMUM AIR FLOW
CHECK
1.Start the engine and warm it up until the engine co olant
is heated to
or higher and then stop the
engine.
PCV valve hose2.Disconnect the PCV valve hose from the intake manif old
n i p p l e .
3. Attach Air Metering Fitting
(0.125 in. orifice)
to the intake manifold nipple.
4.Disconnect the inch idle purge line from the throttle
body nipple. Cap the inch nipple.
5. Connect the scan tool to the data link connector .
6.Restart the engine. Allow engine to idle for at least one
minute. All accessories should be off.
7. Using the scan tool, access the ACTUATOR TEST “Minimum Airflow Idle Speed” screen.
8. The following will then occur:
lIdle air control motor will fully close.
lIdle spark advance will become fixed.
l Scan tool displays engine speed.
9. If idle speed is within the range shown in the
Specification chart, throttle body minimum airflow is set
correctly.
Standard value:
(Less than 1,000 miles)
(More than 1,000 miles)
If idle speed is not within the standard value, use the
scan tool to access the special function “Reset AC” screen
and reset the Then carry out step 7 again.
10. If idle speed is above specifications, use the scan tool
to check idle air control motor operation. If idle air control
motor is OK, replace the throttle body.
NOTE
If the throttle body is replaced, reset the IAC.
idle speed is below specifications, shut off the e ngine
and clean the throttle body as follows: (a) Remove the throttle body from engine.
WARNING:
CLEAN THROTTLE BODY IN A WELL-VENTILATED
AREA. WEAR RUBBER OF BUTYL GLOVES, DO
NOT LET CLEANER COME IN CONTACT WITH
EYES OR SKIN. AVOID INGESTING THE
CLEANER. WASH THOROUGHLY AFTER USING
CLEANER.
(b) While holding the throttle open, spray the entir e throttle
body bore and the manifold side of the throttle plate
with cleaner.
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ENGINE
6. If is not correct, troubleshoot and repair
to the table
SymptomP r o b a b l e c a u s eRemedy
l Fuel pressure too lowClogged fuel filter Replace fuel filterl No fuel pressure in fuel returnhose
Fuel leaking return side due to poorReplace fuel pressure regulator
fuel regulator valve seating or settled
spring
Low fuel pump delivery pressure
Replace fuel pump
Fuel pressure too highBinding valve in fuel pressure
regulator
fuel .
Clogged fuel return hose or pipeClean or replace or ‘pipe
7. the scan tool, with ‘the position,
the “Fuel System ,
8. Turn the ignition switch off and
‘gauge reading. Normal does
within 2 minutes! it does, observe the rate
and troubleshoot and repair-according table
SymptomProbable cause Remedy
Fuel pressure drops gradually afterLeaky injector Replace injector
engine is stopped Leaky fuel regulator valve seat Replace fuel pressur e regulator
Fuel pressure drops sharply
Checkvalve in fuel pump is held open Replace fuel pu mp
ately after engine is stopped
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9.Remove fuel pressure gauge and reinstall protective cover
onto fuel rail service valve.