96 Explorer DTC P0154, Replace All 02 Sensors?

Check engine light has come on three times and the code is DTC P0154.
Is it possible to replace one malfunctioning 02 sensor or do all of them need replacing?

Appreciate any guidance, trying to save money its got 108,000 miles on it..

THX

I had the same thing happen with my 97. Each time it was "fixed" I got about 3 miles down the road and the check engine light would light up. The code was for the O2 sensor each time. Only after they replaced the up line and down line sensor did the problem resolve.



Check engine light has come on three times and the code is DTC P0154.
Is it possible to replace one malfunctioning 02 sensor or do all of them need replacing?

Appreciate any guidance, trying to save money its got 108,000 miles on it..

THX