Mitsubishi FUEL Manual page 65

INSPECTION PROCEDURE 22
Too high CO and HC concentration when idling
Abnormal air/fuel ratio is suspected.
MUT-II Self-Diag code
Are diagnosis codes displayed?
Check the ignition timing.
(Refer to GROUP 11A - On-vehicle Service.)
MUT-II Data list
21 Engine coolant temperature sensor. (Refer to P.13A-75.)
MUT-II Data list
13 Intake air temperature sensor (Refer to P.13A-75.)
MUT-II Data list
25 Barometric pressure sensor (Refer to P.13A-75.)
MUT-II Data list
59 Oxygen sensor (rear)
D Transmission: 2nd gear <M/T>, L range <A/T>
D Driving with throttle widely open
OK: 600 - 1,000 mV
MUT-II Data list
11 Oxygen sensor
OK: 600 - 1,000 mV when racing suddenly.
MUT-II Data list
11 Oxygen sensor
OK: Repeat 0 - 400 mV and 600 - 1,000 mV alternately when
idling.
Check the fuel pressure. (Refer to P.13A-85*.)
Check the following items.
D Check the injectors for operation sound.
D Check the injectors for fuel leakage.
D Check the ignition coil, spark plugs, spark plug cables.
D Check the compression pressure.
D Check the positive crankcase ventilation system.
D Check the purge control system.
D Check the EGR control system.
Check the trouble symptom.
Replace the catalytic converter.
NOTE:
*: Refer to the '97 GALANT Workshop Manual (Pub. No. PWDE9611)
MPI <4G6> -
No
OK
OK
OK
OK
OK
OK
NG
OK
NG
Troubleshooting
Probable cause
D Malfunction of the air/fuel ratio control system
D Deteriorated catalyst
Yes
Refer to P.13A-8, INSPECTION CHART FOR DIAGNOSIS
CODES.
NG
Check that the crank angle sensor is installed properly.
NG
Check the engine coolant temperature sensor system.
(Refer toP.13A-16, INSPECTIONPROCEDURE FORDIAGNOSIS
CODE P0115.)
NG
Check the intake airtemperaturesensor system.(Refer toP.13A-14,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0110.)
NG
Check the barometric pressure sensor system. (Refer to P.13A-12,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE P0105.)
NG
Check the oxygen sensor (rear) system. (Refer to P.13A-24, IN-
SPECTION PROCEDURE FOR DIAGNOSIS CODE P0136.)
NG
Check the oxygen sensor (front) system. (Refer to P.13A-21, IN-
SPECTION PROCEDURE FOR DIAGNOSIS CODE P0130.)
OK
Replace the oxygen sensor.
Check trouble symptom.
13A-65
NG