hey guys... So i was coming home today from work and noticed my check engine light came on. So i turned around and headed to auto zone to scan it. So the code P0430 came up... I know this has something to do with the cats or o2 sensors. I replaced both upper o2 sensors on both cats about 6 months ago, so i dont think thats the problem. But i did notice now that my car sounds different and it actually pulls better since the check engine light came. I also installed my RV6 v3 J-Pipe this past weekend. I allready searched and came up with no helpfull info.. I'm leaning towards the cat being bad. Not sure which one though. Anyone with any info, would be greatly appreciated...thanks

 

Also i have 144K on her....

 

P0430 Catalyst System Efficiency Below Threshold (Bank 2)
Probably bad cat bank 2 (Radiator Side). Reset and see if it reappears.

 

Ok..will do. Thanks turbonut..

 

Ok, so i didnt reset the code but it disappeared on its own. So , exactly what does this mean?... Still a bad cat or maybe the downstream o2 sensors?

 

Could have been a blip, but more than likely it will return at some point in time, so just drive the car until it or if it ever does reappear again, then you'll need to take action. Most cars that I've seen where people replace the downstream sensor, this has not solved the problem as the cat has gone south and needs replacement. Just looked at a Range Rover that the fellow replaced all 4 sensors in hope that the codes would disappear, but to no avail, he'll need to spend some money and replace the cats.

Some will doubled stack spark plug non foulers and then inserted the downstream O2 sensor into this and it has tricked the OBDII into thinking the exhaust is lean and no abnormalities present.