Mitsubishi Eclipse Workshop Manual page 150

13-82
FUEL -
On-vehicle Inspection
of
MPI Components
TROUBLESHOOTTNG HINTS
Hint
1:
Poor cleaning
of
exhaust gas will
result
if the
oxygen sensor fails.
Hint
2:
lf
the oxygen sensor check has resulted normal but the sensor output voltage
is
out of
specification.f
troubles of parts related
to
air
fuel ratio control
system are suspected.
IExamples]
(1
)
Faulty injector
(21
Air
leaking into the intake manifold through gasket gap.
etc.
(3)
Faulty
air flow
sensor, intake
air
temperature sensor, barometric pressure sensor,
water
temperature sensor
INSPECTION
Using Multi-use Tester (MUTI
Data reading
Engine:
Warm-up
(make
the mixture
lean
by engine speed
reduction, and rich by
racing)
Engine: Warm-up
(using
the orygen
sensor
signal. check the
airlfuel
mixture ratio, and also
check the condition of
control
bV
the
engine
control
unit)
850
r./min.
(idle)
4OO
mV
or
loruer
I
(changesl
600-
1.0O0 mV
2.OOO
r/rnin.
HARNESS INSPECNON
N
Check
for continuity
between orygen
sensor
and control
relay.
.
Control relay connector:
Disconnected
.
Orygen sensor connector:
Disconnected
NOTE
Insert
the probes of the circuit
tester
into both ends of the
harness.
Repair
the
harness.
(@El-
@E)
c
o
Check
for an open-circuit or a short-
circuit
to
earth
betlween
the
engine
control unit and the oxlpen
sensor.
.
Oqygen sensor connectot:
Disconnected
.
Engine
control unit connectot:
Disconneaed
Repair
the
harness.
(@tn-E)
(@E-EB)
@
tlttrubirhl
tlotor
Corpor.tion
Apr.
l99f
PW1,E9010