1990 MITSUBISHI SPYDER sensor

ENGINE Troubleshooting
INSPECTION PROCEDURE 4
The check engine/malfunction indicator lamp remains
illuminated and never goes out.
[Comment]In cases such as the above, the cause is probably t hat the PCM is
detecting a problem in a sensor or actuator, or tha t one of the malfunctions listed at right has
occurred.
Probable cause
l Short-circuit between the check indicator lamp and l Malfunction of the PCM
SCAN TOOL DTC Refer to
INSPECTION CHART FOR DIAGNOSTIC
Are diagnostic trouble codesoutput? TROUBLE CODES
Measure at the combination meter connector lDisconnect the connector, and measure at the harnes s
side.Check the harness wire between meter and PCM
connector. Repair, if necessary.
l Disconnect the PCM connector.
l Continuity between 51 and ground
OK: No continuity
O K
Replace the PCM.
INSPECTION PROCEDURE 5
Cranks, won’t start Probable cause
[Comment]l Malfunction of the ignition system
In cases such as the above, the cause is probably t hat a spark plugs are fouled defective,l Malfunction of the fuel pump system
or that the supply of fuel to the combustion chambe r is defective.
l Malfunction of the injector system
in addition, foreign materials (water, kerosene, et c.) may be mixed with the fuel.
l Malfunction of the PCM
l Foreign materials in fuel
,
Check battery positiv
OK: 8 or hiaher Check the battery. (Refer to GROUP 54 Battery)
OK
Scan tool: Inspection when no initial combustion oc
curs.
(Refer to INSPECTION PROCEDURE 29.)
OK
Can any sound be heard
.
(Refer to
Yes
Check ignition circuit system.
(Refer to INSPECTION PROCEDURE 28.)
OK
Check the injector control circuit. Carry out proce dures 19, 20, 21, in “INSPECTION PROCEDURE
FOR DIAGNOSTIC TROUBLE CODES”.,
Check the following items. l Check the ignition coil, spark plugs, spark plug ca bles.
l Clean the injectors.
l Check if foreign materials (water, alcohol, etc.) g ot into fuel.
l Check the compression pressure.
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INSPECTION PROCEDURE 9
Idle speed is high. (Improper idle speed)
[Comment] lIn such cases as the above, the cause is probably that the intake air volume during idle is’ ltoo great. Intake manifold vacuum leak b o d y
SCAN TOOL DTC
Are diagnostic trouble codes output
NO
07 motor (Refer to
NG
Refer to INSPECTION CHART FOR DIAGNOSTICTROUBLE CODES.
Checktheidleaircontrolmotorcircuit.PROCEDURE FOR DIAGNOSTIC TROUBLE
OK
SCAN TOOLSpecial function
“Reset
Check trouble symptoms.
NG
SCAN TOOL SENSOR NGCheck the engine coolant temperature circuit.(Refer to INSPECTION
OK
SCAN TOOL OUTPUT clutch relay (Refer to
OK
NGCheck the switch and compressor clutch relay to INSPECTION PROCEDURE 26.)
Check the throttle body minimum air flow.
(Refer to
INSPECTION PROCEDURE 10
Idle speed is low. (Improper idle speed) Probable ca use
,
[Comment]l control motor In cases such as the above, the cause is probably that the intake air volume during idling is l
Malfunction of the’ throttle body
too small.
SCAN TOOL DTC
YESRefer to INSPECTION CHART FOR DIAGNOSTIC
Are diagnostic troublecodesoutputTROUBLE CODES.
SCAN TOOL Actuator test
07 motor. (Refer to
OK
NG
PROCEDURE FOR DIAGNOSTIC TROUBLE CODE
SCAN TOOL Special function
“Reset
Check trouble
OK
Check the engine coolant temperature circuit. (Refer to INSPECTION PROCEDURE 36.)
SCAN TOOL INPUT STATE TESTS
list) position switch (transaxle range switch)
(Refer to
OK Checktransaxle range sensorcircuit.
INSPECTION
PROCEDURE 25.)
Check the throttle body minimum air flow.
(Refer to
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INSPECTION PROCEDURE 12 , .
. .
When the engine is hot, it stalls at idle. (Die out )
[Comment]l Malfunction of the ignition In cases such as the above, the cause is probably t hat ignition system, mixture, idle l
air control motor or compression pressure is defect ive.Malfunction control M a l f u n c t i o n o f t h e s y s t e m In addition, if the engine stalls, the cause
mayalso be a defective connector contact.l into intake system
l Improper connector contact
W ere the battery terminals disconnected recently
NO
YES After warming-up, let the engine run at idling for 10 minutes.
SCAN TOOL DTC
Are diagnostic trouble codes output?
NO
SCAN TOOL Actuator test
07 motor. (Refer to
OK YES
N G
Refer to INSPECTION CHART FOR DIAGNOSTICTROUBLE CODES.
Checktheidleaircontrolmotorcircuit. INSPECTIONPROCEDURE FOR DIAGNOSTIC TROUBLE CODE
SCAN TOOL Special function
“Reset
Check trouble symptoms.
NG
Check the injector for operation sound.
(Refer to Check the injector control circuit. Carry out proc edures 20, in “INSPECTION PROCEDURE
FOR DIAGNOSTIC TROUBLE CODES”.
Does the engine stall right
released
NO.
Does the engine stall easily again
YES
Scan tool: Inspection when engine stalls when the e ngine
is warm and idling (Refer to INSPECTIONPROCEDURE 33.)
OK
Check the throttle body minimum air flow (Refer to
While carrying out an intermittent malfunction simulation test (Refer
to GROUP 00 How to Cope with Intermittent Malfunctions), check
for sudden changes in the signals shown below.
l Crankshaft position sensor and
l MAP sensor signal Fuel pump signall Injector drive signal l power supply voltage
Check the following items.
l
Check the ignition coil, spark plugs, spark plug ca bles.
l Clean the injectors.
l Check the compression pressure.
l Check if foreign materials (water, alcohol, etc.) g ot into fuel.
INSPECTION PROCEDURE 13
The engine stalls when accelerating. (Pass out) Probable cause
[Comment]l
Injectors failedIn cases such as the above, the cause is probably m isfiring due to a weak spark, or an inappropriatelMalfunction of the ignition system
air/fuel mixture when the accelerator is depressed.
YESRefer to INSPECTION CHART FORDIAGNOSTIC
Arediagnostic trouble codes outputTROUBLE CODES.
NO
Check the following items.
l Check the ignition coil, spark plugs, spark plug ca bles.
l Clogged injectors

ENGINE (NON-TURBO)>
INSPECTION PROCEDURE 14. .. .
The engine stalls when decelerating.P r o b a b l e c a u s e
[Comment]In cases such as the above, the cause is probably t
hat the intake air volume is insufficient due
to a defective idle air control motor system. l Malfunction of the system
W ere the battery terminals disconnected recently?YES After warming-up, let the engine run at idling for
SCAN TOOL DTC
Are diagnostic trouble codes output?
OK
Refer to I N S P E C T I O N FOR TROUBLE CODES.. .
SCAN TOOL SENSOR07 Throttle position (Refer to
NO
NGCheck the throttle position sensor circuit.
(Refer to INSPECTION PROCEDURE 43.)
Check the following items. l Check the ignition coil, spark plugs, spark plug ca bles.
l Check the throttle body minimum air flow.
INSPECTION PROCEDURE 15
Hesitation, sag or stumble
[Comment]In cases such as the above, the cause is probably t hat ignition system, air/fuel mixture or
compression pressure is defective.
Probable cause
Malfunction of the ignition Malfunction of air-fuel ratio control l Malfunction of the fuel supply l of the EGR. solenoid l P o o r
Are diagnostic trouble
codes output
Check the injectors for opNG
(Refer to Check the injector control circuit. out procedures 20, 21, in’ INSPECTION PROCEDUREFOR DIAGNOSTIC TROUBLE CODES”.
Scan Tool: Inspection when hesitation, sag, stumble or pooracceleration occur. (Refer to INSPECTIONPROCEDURE 34.)
OK
Check the fuel pressure. (Refer to
OK
Check the following items.l Check the ignition coil, spark plugs, spark plug ca bles.
l Check the EGR system.
l Check the compression pressure.
l Check the fuel filter or fuel line for clogging.
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INSPECTION PROCEDURE 16 . ,
Acceleration shock ,
[Comment] Malfunction of the ignition systemIn cases such as the above, the cause is probably that there is an ignition leak accompanyinglthe increase in the spark plug demand voltage durin g acceleration.Improper control of reduction stiifting.
Are diagnostic trouble codes output
NO YES
Refer to INSPECTION CHART D I A G N O S T I CTROUBLE CODES.
Check the following items.
l
Check the ignition coil, spark plugs, spark plug ca bles.
l Check for occurrence of ignition leak.
l Check the torque reduction link (wire) between the PCM and TCM.
INSPECTION PROCEDURE 17
Deceleration shock Probable cause
[Comment]Malfunction of the system is suspected.l Malfunction of ‘system
III
Are diagnostic trouble codes output
NO
YESR e f e r t o C H A R T F O R TROUBLE CODES.
SCAN TOOL Actuator test
07 motor. (Refer to PROCEDURE FOR DIAGNOSTIC TROUBLE CODES
SCAN TOOL Special function“Reset
Check trouble I
N G
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Check the throttle body minimum air flow.
(Refer to
SCAN TOOL SENS
07 Throttle position (Refer to NGl Check the throttle position sensor
(Refer to INSPECTION PROCEDURE 43.)

ENGINE Troubleshooting
INSPECTION PROCEDURE 20
Knocking
[Comment]l Defective knock sensorIn cases such as the above, the cause is probably t hat the detonation control is defective or l
the heat value of the spark plug is inappropriate. Inappropriate value of the
YES
Are
diagnostic troublecodesRefer to INSPECTION CHART FOR DIAGNOSTIC
outputTROUBLE CODES.
NO
SCAN TOOL SENSORNG
09 Knock sensor volts (Refer toCheck the knock sensor circuit (Refer to INSPECTION
PROCEDURE FOR DIAGNOSTIC TROUBLE
OK
Check the following items. l heat ranae
l Check ‘if (water, alcohol, etc.) got into fuel.
Dieseling cause
[Comment]Fuel leakage from injectors is suspected. l
Fuel leakage from injectors
Check the injectors for fuel leakage.
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INSPECTION PROCEDURE 22
Too high CO and HC concentration when idling
[Comment]Abnormal air-fuel ratio is suspected.
cause
of the air-fuel ratio control system.l Deteriorated catalyst .
SCAN TOOL DTC
Are diagnostic trouble codes output Refer to INSPECTION CHART FOR DIAGNOSTICTROUBLE CODES.
NG
27 Intake air temperature sensor. (Refer to Check the intake air temperature sensor circuit.
( R e f e r t o 3 9 . ) .
N G Check the MAP sensor circuit11MAP sensor reading. (Refer to (Refer to INSPECTION PROCEDURE 40.)IOK
SCAN TOOL SENSOR READ TESTS (Data list)
83 sensor volts (rear) (Refer to l Transaxle gear range l Driving with the throttle wide open
O K :
OK
SCAN TOOL SENSOR READ TESTS (Data list)
02 sensor volts (front) (Refer to OK: 1 when suddenlv
N G Check the heated oxygensensor (rear) circuit.
(Refer to INSPECTION PROCEDURE 41.)
NG
02 sensor volts (front) (Refer to
Check the fuel pressure. (Refer to
OK
Check the following items.
l Check the injectors for operation sound.
l Check the injectors for fuel leakage.
l Check the ignition coil, spark plugs, spark plug ca bles.
l Check the compression pressure.
l Check the positive crankcase ventilation system.
l Check the evaporative emission control system.
l Check the EGR system.
NG
Check trouble symptom.
N G
Replace the three-way catalytic converter.
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ENGINE ( N O N - T U R B O ) >
INSPECTION PROCEDURE 25
Transaxle range sensor circuit
[Comment]The transaxle range sensor inputs the condition of the selector lever, i.e. whether it is in or range or in some other range, to the PCM.
The PCM controls the idle air control motor based o n this input.Improper connector contact, open circuit
Check the transaxle range sensor. (Refer to GROUP On-vehicle Service.) Replace.
lDisconnect the connector,and measure atthe harness
A-l
OK
Check trouble symptom.
OK
Replace the PCM.
Check harness wire betweenN G
PCM transaxle rangesensor connector.
O K
Replace the PCM.
,
INSPECTION PROCEDURE 26
A/C switch and A/C compressor clutch relay system
motor, and also operates the A/C compressor magneti c clutch.Probable cause
l Malfunction of A/C control l Malfunction of A/C switch Improper connector open short-circuited harness wire
l Malfunction of PCM
NG
OKCheck the A/C compressor clutch relay.
Measure at the PCM
l
(Refer to GROUP 55 On-vehicle Service.)
Disconnect the connector, and measure at the harnes s
Replace
Check the
system. (Refer to GROUP 55
side.lVoltage between 64 and ground, and 38 and ground(Ignition switch: ON)
(A/C switch: ON)
OK: Battery positive voltage
l Connect a jumper wire between 64 and ground.
(Ignition switch: ON)
(A/C switch: ON)
OK: A/C compressor clutch turns ON.
OK1NG RepairA-l 06,A-l 07
OK
Check trouble symptom.
Replace the PCM.
NG
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