[78clow]

I have a 2013 Hyundai Veloster in trying to identify the O2 sensors upstream and downstream. here's a pic of a diagram showing both sensors. One orange highlight and one blue highlight.

 

[RPW00Mirage]

closer to the motor is upstream, so that's orange. the other is further away, so that's downstream.

 

[78clow]

Thank you so much. That's what I thought but I wanted to be 100% sure.