P0135

Check engine light has been flashing on and off for a while now (I know I have a cat that is on it's way out the door so I ignored it) I finally scanned it, and it read code P0135 which is O2 sensor malfunction sensor 1 bank 1. Is this related to the catalytic converter being bad? How can I fix this? Note: when I scanned the CEL was off.

 

I'm no expert but I imagine it's related to the catalytic converter going out, IIRC there's an 02 sensor located just before the cat

 

I believe the Bank 1 Sensor 1 is the 02 sensor BEFORE the cat. Usually when a catalytic convertor goes bad, you can hear it rattle. But if you have ignored the Bank 1 02.....you may have clogged it up. Replace the 02 and go from there.