Front Oxygen (A/F) Sensor: Inspection

1. Check that the front oxygen (A/F) sensor has no deformation, cracks or other damages.
2. Measure the resistance between front oxygen (A/F) sensor terminals.

Fig 1: Measuring Resistance Between Front Oxygen (A/F) Sensor Terminals

Courtesy of SUBARU OF AMERICA, INC.

Terminal No.	Standard
2 and 3	2.5-4.0Ω (at 20°C (68°F))