Mitsubishi Pajero Pinin 1999, Workshop Manual

Page: 119 / 919

GDI ±
Troubleshooting
13A-47
INSPECTION PROCEDURE 7
Unstable idling (rough idle, hunting) Probable cause
This malfunction is probably caused by a faulty ignition system, improper air/fuel
ratio, a faulty electronic-controlled throttle valve system, improper compression
pressure, etc. As many causes can be suspected, diagnose from easier items.
D
Malfunction of the ignition system
D
Malfunction of the air/fuel ratio control system
D
Malfunction of the electronic-control throttle valve
system
D
Improper compression pressure
D
Air sucking into the air intake system
Has the battery been disconnected recently?
Yes
Warm up the engine, and then let it run at idle for approx. ten
minutes.
No
MUT- II Self-Diag code
Is a diagnosis code displayed?
Yes
Refer to P.13A-14, INSPECTION CHART FOR DIAGNOSIS
CODES.
No
Does the engine idle speed fluctuates excessively (excessive
hunting)?
Yes
Clean around the throttle valve. (Refer to P.13A-92.)
No
MUT-
II
Data list
14 Throttle position sensor (2nd channel) (Refer to P.13A-72.)
NG
Check the throttle position sensor (2nd channel) system. (Refer
to P.13A-18, INSPECTION PROCEDURE FOR DIAGNOSIS
CODE 14.)
OK
MUT-
II
Data list
79 Throttle position sensor (1st channel) (Refer to P.13A-75.)
NG
Check the throttle valve position feedback system. (Refer to
P.13A-37, INSPECTION PROCEDURE FOR DIAGNOSIS CODE
92.)
OK
MUT- II Data list
26 Accelerator pedal position switch (Refer to P.13A-73.)
NG
Check the accelerator pedal position switch system. (Refer to
P.13A-65, INSPECTION PROCEDURE 27.)
OK
MUT-
II
Data list
13 Intake air temperature sensor (Refer to P.13A-71.)
NG
Check the intake air temperature sensor system. (Refer to
P.13A-17, INSPECTION PROCEDURE FOR DIAGNOSIS CODE
13.)
OK
MUT-
II
Data list
25 Barometric pressure sensor (Refer to P.13A-73.)
NG
Check the barometric pressure sensor system. (Refer to P.13A-23,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE 25.)
OK
MUT-
II
Data list
21 Engine coolant temperature sensor (Refer to P.13A-72.)
NG
Check the engine coolant temperature sensor. (Refer to P.13A-19,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE 21.)
OK
MUT-
II
Actuator test
08 Purge control solenoid valve (Refer to P.13A-76.)
NG
Check the purge control solenoid valve system. (Refer to P.13A-68,
INSPECTION PROCEDURE 30.)
MUT-
II
Data list
11 Oxygen sensor
OK: 600 ± 1,000 mV when the engine is suddenly raced
NG
Check the oxygen sensor system. (Refer to P.13A-15, INSPEC-
TION PROCEDURE FOR DIAGNOSIS CODE 11.)
OK
OK
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