Question about 2004 Ford Focus

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Engine light on and idling rough

I took my ford focus to a local auto parts store to have them check the codes. The code reader said that I needed to replace the O2 sensor so I did but it did not solve the problem. What else can I do

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  • wtmorgan332 Jan 16, 2009

    Thanks for your help. I only replaced the up flow 02 sensor so you think that there are 2 sensors. That is helpful info thanks again



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What code(s) are coming up when scanned?

You said you changed "the" O2 sensor? I believe your vehicle has two O2 sensors. One is located upstream from the catalytic converter and the other is located downstream from it. Is it possible that you changed one and left the other?

Posted on Jan 15, 2009

  • Chris Hall
    Chris Hall Jan 19, 2009

    Yes. I checked Chilton, as well as the "major" parts suppliers. The all list two O2 sensors for your vehicle.



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