Cat Converter
 

I got a P0420 message on the car. Most likely it is the cat converter but I'm hoping it's just an 02 sensor. The car recently passed emissions. Is this mean that the cat converter is still fine? I looked online for parts and there is a place on Kijiji that sells direct fit cats for $120. Has anyone gone to this place before? It's on Magnetic Drive in North York. The ad doesn't give a name of the store.

toronto.kijiji.ca/c-cars-vehicles-auto-parts-tires-other-parts-accessories-Audi-A4-Avant-1-8L-Catalytic-Converter-2002-2004-W0QQAdIdZ379200104]]New and used - auto parts and accessories for sale Toronto (GTA). Free car part & auto / truck accessories classifieds on kijiji.ca[/url