Oxygen sensors?

2003 VOLKSWAGEN JETTA
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JAMAICAHAYES
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  • 1 POST
I was driving my car the other day and noticed the check engine light stayed through my entire drive to work. I also noticed that the car temp gauge remained in the high level the entire day, even if the car had sat for a period of time. I checked the oil level and that was normal, but when I checked the coolant level it was about 1/2 an inch below the line. Could the coolant being low have triggered the check engine light? Also, they told me the oxygen sensor are bad can you help me find them?

Thank you.
Sep 24, 2008 at 2:13 PM
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SQM
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Hello,

First of all, low coolant level can make an engine run hotter than usual. Be sure to top off the coolant reservoir with appropriate coolant.
Your vehicle has 2 oxygen sensors. One is before the catalytic converter (closer to the engine and the converter), second one is after the catalytic converter (further from the engine)

The check engine light typically tells you which is the defective sensor.
Do you know the trouble codes? This will point us to the right direction.

https://www.2carpros.com/articles/how-an-oxygen-sensor-works

https://www.2carpros.com/articles/how-to-test-an-oxygen-sensor-02-sensor

I have attached the locations for both of the oxygen sensors.

Please let me know of any questions.

Thank you.
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Jul 28, 2021 at 9:53 PM