Faulty oxygen sensor question

[m1eller]

Hello - I'm new to this forum and have a quick question about my O2 sensor. I don't know which one is faulty (yet) but I am considering buying an aftermarket O2 sensor for about $35 and plugging it in. My CEL came on and the local garage ran a diagnostic for $75 and found that the O2 sensor was the issue - they found the clip to be loose so they cleaned it & reattached it. Next day the light was back on, so the mechanic was talking about a $250-300 O2 sensor to fix the problem.
Anyone have any opinion on the aftermarket O2 sensors? I will ask the mechanic which one it was (before or after the cat).
Thanks

[murphy390]

First go to AutoZone and they will pull the code for you at no charge and you'll know which sensor needs to be replaced. You have plenty of options but you can first check with the sponsors of this site. I've replaced several in my Camry's and Maxima and it's usually an easy DIY job. So far I haven't had to replace them in my Saab but that day will come.

Depending upon access to the sensor you may need to get the special O2 sensor socket which allows for the wires. They're about $10 at any auto parts store.