My 2000 Sonata has the check engine light on. I had the catalytic converter replaced recently.
It could also be a faulty O2 sensor that can trigger the check engine light. If you have an AutoZone nearby I would have the check the fault codes. This will be a more accurate diagnosis of the problem. They will run the fault code as well as reset the CEL (Check Engine Light). If the CEL stays off after the reset then you you are in good shape. If the light turns back on then you know you should replace what triggered the fault code. I hope that helps
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