Oxygen sensor or Catalytic converter? | Ford Escort Owners Association (FEOA)

Oxygen sensor or Catalytic converter?

Discussion in 'Tech & Repair' started by MissMarie, Oct 15, 2019.

  1. MissMarie

    MissMarie New Member

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    So I have a bit of an issue, my idiot light has been on now for a few days so I took it in to the local parts store. The person ran the test but he couldn't tell me whether it was the sensor or the converter, so what the heck do I do?? Kinda spendy to replace both, so how can I pinpoint which one is going out? It's a 2003 escort ZX2, any suggestions would be really appreciated.
  2. Gamer92

    Gamer92 FEOA Donator

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    How many miles? What code did he say it's throwing?
    zzyzzx likes this.
  3. Swift

    Swift FEOA Donator

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    What exactly was the code?
  4. zzyzzx

    zzyzzx FEOA Member

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    What code?
    How be many miles are on the car?
    Has the oxygen sensor been replaced before?
    Other than the dash light being on, is the car otherwise running normally?
  5. marclar

    marclar Moderator Staff Member

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    thats like going to the dr and saying... "my arm hurts" and just pointing to it. we need specifics. cat code and o2 codes take different testing and equipment. that is why parts stores pull codes, its so they can sell you parts based off of the code.

    need the exact specific codes .
  6. Missile99

    Missile99 FEOA Member

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    If your car is still running strong all through the revs and the plugs have always burned clean, then typically an o2 sensor is most likely worn out. It's only got one? I can't remember if my '96 1.9 had one or two. I think they all have up- and downstream sensors nowadays. Catalytic converters are not something you should have to replace unless the material is crumbling or melting from being clogged. It's tough to get multiple choices with parts store codes. Maybe an exhaust shop can tell you about your exhaust flow or bad emissions?
  7. denisond3

    denisond3 Moderator Staff Member

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    Any 3rd gen Escort would have two oxygen sensors - the upstream close to the exhaust manifold, the downstrem being further back under/behind the engine. The upstream one usually would get feeble first. The downstream one would probably go out after the car had 200k miles on it. Either one of them having gone feeble would be likely to turn the Check Engine Light on.
    And its true; if the engine has always been running well, not misfiring much, then the catalytic converter should still be okay.
  8. Bas1c973sco

    Bas1c973sco FEOA Member

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    If it is the catalytic converter, cheap POSSIBLE fix is using Cata Clean from the brand CRC, it’s meant to clean it out. We need to know the code to help you better also be aware that oxygen sensors and read rich or lean for other reasons than just being bad. Once we know the code then we get you in the right direction.


    Sent from my iPhone using Tapatalk
  9. MissMarie

    MissMarie New Member

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    Thank you for the info and the last place I took I forgot to ask for the code so I will try again and get the code this time. Should I wait using the cats clean or could I use it before I can get the code?
  10. Joey_Twowagons

    Joey_Twowagons FEOA Member

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    I would get the code read before the treatment, then again a few hundred miles after the treatment to see if there's a change. They'll scan the car for free at the parts store, right?
  11. zzyzzx

    zzyzzx FEOA Member

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    I still want to know the mileage on the existing O2 sensors.
    That, and if not original and a known good aftermarket brand, I would still drive with an OBDII reader that read and recorded live data.

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