Montero SR 4WD V6-3.5L SOHC (1997)
Oxygen Sensor: Testing and Inspection
Federal
TROUBLESHOOTING HINTS
Hint 1:
The exhaust gas purification performance will worsen it there is a malfunction of the heated oxygen sensor.
Hint 2:
If the heated oxygen sensor output voltage is outside the standard value even though the results of the checking of the heated oxygen sensor are
normal, the cause is probably a malfunction of a component related to mixture control.
[Examples]
(1) Malfunction of injector
(2) Air is drawn into the intake manifold from a leaking gasket, etc.
(3) Malfunction of volume air flow sensor, intake air temperature sensor, barometric pressure sensor or engine coolant temperature sensor
INSPECTION
Using Scan Tool
<Heated Oxygen Sensor (front)>
<Heated Oxygen Sensor (rear)>
HARNESS INSPECTION
STEP 1. Check for continuity between the heated oxygen sensor and the MFI relay.
-
MFI relay connector: Disconnected
-
Heated oxygen sensor connector: Disconnected
NOTE:
-
Touch the ohmmeter probes to both ends of the harness.
OK: GO TO STEP 2
NG: Repair the harness. (A1 - C1, B1 - C1)