1990 MITSUBISHI SPYDER coolant temperature

ENGINE (NON-TURBO)> Troubleshooting
Scan tool 119
Code General scan tool
No. 71Fuel System LeanProbable
51
[Comment]l Engine coolant temperature sensor Backgroundl The PCM monitors the fuel system for compliance wit h emission standards.l
Intake air temperature sensor failed- l Head gasket Range of Check
l Exhaust manifold cracked
l Engine coolant temperature is greater than l Injectors failed
l Closed loop operation
l MAP sensor failed
Set Condition
l Heated oxygen sensor failedlThe test fails if the fuel control system increases pulse width by 25% long term memory
and 12% short term compensation due to a lean condi tion.l
Fuel pressure regulator l l Fuel filter or fuel line blocked
l Fuel pump failed (insufficient discharge)
l Incorrect fuel used
__
l PCM failed
NGSCAN TOOL SENSOR READ TESTS (Data list)
05 Engine coolant temperature sensor (Refer to
SCAN TOOL SENSOR READ 27 Intake air temperature sensor to
SCAN TOOL SENSORREAD11 MAP sensor reading (Refer to
I
NG
Check the engine coolant temperature circuit.
(Refer to INSPECTION PROCEDURE 38.)
Check the intake air temperature circuit.(Refer to PROCEDURE 39.)
Check the MAP sensor circuit.
( R e f e r
63 Oxygen sensor volts (rear) (Refer to l Transaxle: gear range
SCAN TOOL SENSOR READ TESTS (Data list)
02 Oxygen sensor volts (front) (Refer to
OK: during sudden racing
NG Check the heated oxygen sensor (front) circuit.(Refer to INSPECTION PROCEDURE 42.)
SCAN TOOL SENSOR READ TESTS (Data list)
02 Oxygen sensor volts (front) (Refer to
OK: Repeat and alternately whenidling.
Check the fuel pressure. (Refer to
OK
Check the following items.
l Check the injectors for operation sound.
,
l Clean the injectors.
l Check the positive crankcase ventilation system.
l Check the fuel pump.
lCheck the fuel filter and fuel line for blockages.
l Check for exhaust gas leaks.
l Check for contamination (water, kerosene, etc.) in the fuel.
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(NON-TURBO)>
Scan tool 126
Code General scan tool Downstream Shorted to
No. 38Voltage
21
[Comment]l Heated oxygen sensor failedBackgroundlDownstream heated oxygen sensor requires a heater c ircuit for proper operation.l harness and connectors
l
The heater circuit is supplied with battery voltage through the relay relay).l .
lA failure in the sensors heater circuit prevents it
from providing accurate data to the lIf the PCM monitors more than 1.2 volts, the sensor has shorted to heater circuit voltage.Range of Checkl Two or more minutes after the engine startsl Engine coolant temperature: or moreSet Conditionl Heated oxygen sensor output voltage is more than 1. 2 for 3 seconds.
NGCheck the heated oxygen sensor (rear). (Refer to R e p l a c e
OKNGCheck the following Repair
OK
Check trouble symptom.
NG
Check the harness wire between the PCM and the hea ted NG
sensor (rear) connector.
OK
Replace the PCM.
Scan tool 128
Code General scan tool Closed Loop Temperature
No.
17
[Comment]l Thermostat fully openBackgroundl Engine coolant temperature sensorl The fuel control system remains in open loop due to low engine lEngine coolant temperature sensor lThis DTC will be stored if engine temperature remains for 10 minutesimproperly connected
of operation and no engine coolant temperature sens or code has been set.
l PCM failed,
Range of Check
l Engine: running ,Set ConditionlEngine coolant temperature does not exceed after 10 minutes have passed ,
since starting the engine.
,
NGCheck the thermostat. (Refer to GROUP 14 Thermostat.) Replace
OKNG Replace
Check the following connectors:NG Repair
Check trouble symptom.
temperature
sensor connector. OK
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ENGINE (NON-TURBO)>
Scan tool 129.
C o d e G e n e r a l s c a n t o o l D o w n s t r e a m Stays at
No. 40. 21
[Comment]Backgroundl Heated oxygen sensor (rear) ,
l Sensor output voltage is checked. l
Sensor signal circuit open
PCM failedlIf voltage stays at center instead of switching, an open circuit is likely.Range of Check
. .l 2 minutes after starting enginel Engine coolant temperature: More than Set Condition.lNeither rich nor lean condition is detected from th e downstream heated oxygen sensor .
input. (Voltage is 0.5 volts for 1.5 minutes)
Check the heated oxygen sensor (rear)
OK
NG
N G
Replace
Repair
OK
Check trouble svmptom.
NG
Check the harness wire between thesensor (rear) connector.
OK
NG Repair
Replace the PCM.
Scan tool 132
Code
No.
scan tool Throttle Position Does Not Agree
Map
24
[Comment] Background
lThis DTC indicates a failure in the rationality che ck comparing MAP values to throffleposition.Range of Check
l Engine speed: less than 1,500
l Subtract MAP value from atmospheric pressure:
more than 13 (19 psi) [when atmospheric pressure is more than 7 7 (11 psi)]
more than 6 (0.9 psi) [when atmospheric pressure is less than 77 (11 psi)]
Set Condition
l Throttle position sensor output voltage is 3.75-4.7 1 V.
Range of Check
l Engine speed: more than 1,500
l Vehicle speed: more than 25 mph
l Subtract MAP value from atmospheric pressure: less than 13 (19 psi)
Set Condition
l Throttle position sensor output voltage is
V.
SCAN TOOL SENSOR READ TESTS (Data list)
07 Throffle position (Refer to
OK
. _ -
SCAN TOOL SENSOR READ TESTS (Data list)
69 MAP gauge reading (Refer to
t -
OK
Replace the PCM.
. sensor failed position sensor related lMAPlM A P related circuit
.
Check the throffle position sensor system. (Refer. I N S P E C T I O N P R O C E D U R E FO RC O D E (Refer to I N S P E C T I O NPROCEDUREF O R D I A G N O S T I C T R O U B L E C O D E
Check the MAP sensor system. (Refer to INSPECTIONP R O C E D U R E F O R D I A G N O S T I C T R O U B L E (Refer to INSPECTION FOR DIAGNOSTIC TROUBLE CODE
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ENGINE Troubleshooting .
Scan tool 138
Code General scan tool
No. Not
25
[Comment]Range of Check
l Engine:
l Vehicle at rest and the brake appliedSet Conditionl speed differs from target idle by 200 for 12 seconds. l
Idle air control motor failed
l motor related circuit .
SCAN TOOL SENSOR READ TESTS (Data list)
12 position (Refer to Check the air control motor. (Refer to
OK
Check the throttle body minimum air flow. (Refer to
Code
No. R e l a y
General scan tool High Speed Radiator Fan Control
[Comment]
Background
lThe high speed radiator fan relay controls the high speed operation of the radiator fan.lOne side of the relay control coil is supplied with 12 volts when the switch is
turned to the ON position.
lThe circuit is completed when the other side of the relay coil is grounded by the PCM.lThe PCM grounds the relay control circuit depending on engine coolant temperature and/or A/C compressor condition, etc.
Range of Check
l Battery voltage: 10
or more
l Ignition switch: ON
Set Condition
lAn open or shorted condition is detected in the hig h speed radiator fan relay control circuitfor 3 seconds.
Probable cause
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l Relay open or l Ignition switch output lLow speed radiator fan relay control circuit
open or shorted
NGMeasure at the PCM connector Check the radiator fan circuit.lDisconnect the connector, and measure at harness side. Voltage between 69 and ground(Ignition switch: ON),.
OK: Battery positive voltage .,
l
Connect a jumper wire between 69 and ground(Ignition switch: ON)
OK: Radiator fan runs at high speed.
OK
Check the following connector: N G Repair
OK
Check trouble symptom.1
NG
Replace the PCM.

E N G I N E
Scan tool 154
C o d e G e n e r a l s c a n t o o l T e m p e r a t u r e S e n s o r
No.Voltage Too High
44
[Comment]
Backgroundl Battery temperature sensor l PCM failedBattery temperature input is used to adjust the gen erator charging rate based upon the ambienttemperature around the battery.Range of CheckIgnition switch: ON
Set Conditions .
The sensor voltage remains more than 4.9 for 3 seconds.
Replace the PCM.
Scan tool 155
C o d e G e n e r a l s c a n t o o l U p s t r e a m S h o r t e d t o
No. G r o u n d
[Comment]
Background
lWhen the heated oxygen sensor temperature is low, t
he sensor has the same electrical
characteristics as an insulator.
lThe heated oxygen sensor output signal line is rest ricted to That is why the line voltageis approx. when the heated oxygen sensor temperature is low.lIf the heated oxygen sensor output signal line is grounded, its voltage will become low.
Range of Check
l Engine coolant temperature when the engine starts:
or less
l Within three seconds after the engine
Set Conditions
The heated oxygen sensor output signal line is or less.
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l
.
Upstream, heated oxygen sensor failed
Wiring harness and connectors failed PCM failed
NGCheck the harness wire between the PCM and upstream heated Repair
oxygen sensor connector.
OK
Replace the PCM.

,
-- Scan tool 156,I
C o d e G e n e r a l s c a n t o o l D o w n s t r e a m to
No. G r o u n d
21
[Comment]l Downstream heated oxygen Backgroundl harness and connectors lWhen the heated oxygen sensor temperature is low, t he sensor has the same electrical
l PCM failed characteristics as an insulator.lThe heated oxygen sensor output signal line is That is is approx. when the heated oxygen sensor temperature is low.If the heated oxygen sensor output signal line is g rounded, will become lRange of checkl Engine coolant temperature when the engine starts: or lessl Within three seconds after the engine starts
Set Conditions
The heated oxygen sensor output signal line is
or less.
NGCheck the harness I .oxygen sensor connector.. , ,
OK
Replace the PCM.
11
[Comment]Background , connectedlAfter the engine has been started, the PCM maintain s an expected camshaft port l position
Scan tool 157,General scan toolIntermittent Loss of CMP CKP Probable cause
value. connectedlAt every crankshaft leading edge, this value is updated to reflect the expected
.Camshaft position sensor change in the cam level.
l lAt every crankshaft trailing edge, this value is compared to the true port level. sensor improperly lIf there is a disagreement between two values, then the diagnostic code isset.l sensor
Range of Check
l Engine: running
Set Condition
l Cam and crank signals have been out of sync, than times.
N GCheck the following connectors:. A-l 06
OK
__Check no cam sync. signal at PCM. (Refer to INSPECTION PROCEDURE FOR DIAGNOSTIC TROUBLE
CODE.
Check no crank reference signal at PCM. (Refer to INSPECTION PROCEDURE FOR DIAGNOSTIC TROUBLE
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E N G I N E
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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ENGINE (NON-TURBO)>
INSPECTION PROCEDURE 29
S c a n t o o l : I n s p e c t i o n w h e n n o i n i t i a l c o m b u s t i o n oc c u r s .
SCAN TOOL SENSOR READ TESTS
list)
10 Battery voltage (Refer to
OK
Check the power supply system and circuit.
(Refer to INSPECTION PROCEDURE 23.)
Does the camshaft rotate, while cranking the engine (When oil filler cap is removed.) Check fming belt for breakage.’
SCAN TOOLDTC
INSPECTION PROCEDURE FOR DIAGNOSTIC TROUBLE CODES.Are the diagnostic trouble codes output( R e f e r t o
SCAN TOOL SENSOR READ TESTS (Data list) Check no crank reference signal
at’(Refer to 17 Engine speedINSPECTION TROUBLE CODES Cranking speed is displayed.
SCAN TOOL Actuator teNGCheck the fuel pump system:51 Fuel pump relay (Refer to (Refer to INSPECTION 24.)
SCAN TOOL SENSOR
Check theengine coolant temperatureSensor(Refer to INSPECTION PROCEDURE 38.)
INSPECTION PROCEDURE 30
Scan tool: Inspection when incomplete combustion o ccurs.
SCAN TOOL
Refer to C H A R T F O R Are diagnostic trouble code outputTROUBLE CODES.
SCAN TOOL Actuator NG
51 Fuel pump relay (Refer to Check the fuel pump system. (Refer to INSPECTION PROCEDURE 24.)
OK ,
SCAN TOOL SENSOR NGCheck the engine coolant temperature sensor circuit .
(Refer to INSPECTION PROCEDURES 38.)
INSPECTION PROCEDURE 31.
Inspection when hunting occurs.
,
Check the body minimum air flow.
(Refer to
Check trouble symptom.
NG
Inspect air intake system for vacuum leaks.
l Broken intake manifold gasket
l Broken air intake hose
l Broken vacuum hose
lPositive crankcase ventilation valve does not opera te.
T S B R e v i s i o n