This is the only code i'm getting (aside from some code about the airbag). P0420 .. If i clear it, it comes back a day later. The catalytic converter is only about a year or so old. What could cause this problem? The only thing I can think of is that it started fairly soon after I did a top engine cleaner (stuff you put in the TB while engine idling and it cleans it out, makes a super nasty smell and smoke heh). Could that have toasted an oxygen sensor or something? IT says it's oxygen sensor safe.. either that or it's just a coincidence.. Anyone else seen this code and nothing else related pop up?

Have you tried switching to different gas? Bad gas can do this sometimes. Was the new converter an OEM or Corsa/aftermarket? Have you noticed your gas mileage going down, or has it seemed like the motor is working harder lately? It's possible either the pre- or post-converter O2 sensor is dying, but I would expect to see a code for one or the other in the very near future if that's the case. If you've had gas that had lead or sulphur in it, that can chew up a cat pretty quickly, or the new cat didn't have the same capacity or surface area that the original did perhaps. That's all I can think of at the moment.

M C
:cheers: