Mitsubishi 3000GT Service Manual page 247

MULTIPORT
FUEL INJECTION - Components
h AD998464
TSB Revision
On-Vehicle Inspection of MFI
SENSOR INSPECTION
(1) Disconnect the heated oxygen sensor connector and con-
nect the special tool, Test Harness, to the heated oxygen
sensor connector.
(2) Check that there is continuity [approx. 20 Q at 20% (SSOF)]
across terminals (1) and (3) of the heated oxygen sensor
connector.
(3) If there is no continuity, replace the heated oxygen sensor.
(4) Warm up the engine until the engine coolant temperature
becomes 80°C (176°F) or higher.
(5) Using jumper wires, connect terminals (1) (red clip of
the special tool) and (3) (blue clip) of the heated oxygen
sensor connector to battery (+) and (-) terminals respec-
tively.
Caution
Ensure that the jumper wires are connected correctty,
as wrong connections result in a broken heated oxy-
gen sensor.
(6) Connect a digital voltmeter across terminals (2) (black
clip of the special tool) and (4) (white clip).
(7) Race the engine repeatedly and measure the output volt-
age of the heated oxygen sensor.
Heated oxygen
Engine sensor output
voltage
When engine is
raced
(8) If the measurements are not as specified, defective heated
oxygen sensor is suspected.
INSTALLATION
(1) For removal and installation of heated oxygen sensor,
refer to GROUP 15 - Exhaust Manifold.
(2) Tighten the heated oxygen sensor to specified torque.
Remarks
When the air-fuel mixture
becomes richer as a result
of repeated racing, the
heated oxygen sensor
should output a voltage of
1 .O V.