Mitsubishi Eclipse 1990 Service Manual page 443

Scan tool 112
Code General scan tool Catalytic Converter Efficiency
No.
64
[Comment]
Background
During normal closed-loop operation, the PCM monitors the catalytic converter for hydrocar-
bon conversion (HC) efficiency.
When HC conversion drops below 60 percent efficiency, the PCM stores a diagnostic
trouble code.
Range of Check
Engine coolant temperature greater than
Vehicle speed greater than
Open throttle
Closed loop operation
Engine speed between 1248 and 2400
MAP voltage between 1.50 and 2.60
Set Condition
The switch (Lean/Rich) rate of the rear heated oxygen sensor reaches 70% of the front
sensors switch rate.
Check the exhaust system.
Check for cracks or exhaust leaks.
SCAN TOOL SENSOR READ TESTS (Data list)
63 Downstream heated oxygen sensor volts
(Refer to
Transaxle: range
with wide-open throttle
OK: 600 1000
SCAN TOOL SENSOR READ TESTS (Data list)
02 Upstream heateed oxygen sensor volts
(Refer to
OK: 600 1000 during sudden racing
SCAN TOOL SENSOR READ TESTS (Data list)
02 Upstream heated oxygen sensor volts
(Refer to
Repeat 0 400 and 600
OK
idling.
Replace the heated oxygen sensor (rear).
Check trouble symptom.
Check trouble symptom.
Replace the PCM.
ENGINE (NON-TURBO)>
Failure
for 2 minutes
OK
OK
1000 alternately when
OK
NG
NG
Revision
Replace the exhaust manifold.
NG
Check the heated oxygen sensor (rear) circuit
(Refer to
NG
Check the heated oxygen sensor (front) circuit (Refer to
INSPECTION PROCEDURE 42).
NG
Replace the heated oxygen sensor (front).
,
Catalytic converter
Heated oxygen sensor failed
E x h a u s t
. failed
PCM failed
.
INSPECTION PROCEDURE
, ,
.
1