2002 Ford Focus 0171 code

[tacomabobd]

Hi all,

I have a 2002 Ford Focus LX. The 0171 code came up and I replaced both o2 sensors. I cleared the code and it came back in a few days. Does anyone have any ideas?

Thanks in advance
Bob

[DCHAS]

Originally Posted by tacomabobd

Hi all,

I have a 2002 Ford Focus LX. The 0171 code came up and I replaced both o2 sensors. I cleared the code and it came back in a few days. Does anyone have any ideas?

Thanks in advance
Bob

Check carefully for vacuum leaks hoses, pcv hose etc.

[3100]

- agree you have unmetered air coming into engine, check all hoses, air intake, and o2 sensor wires for melted wires/short to grnd.