I've had the pesky dash light on screaming at me that there is a p0420 code being thrown on my '04 Prius. Car runs fine and I'm very tired of this dash light staring me in the face. Somewhere in an older thread somebody wrote that a spark arrestor screwed into a o2 sensor bung might be the answer to the problem. Having the sensor a half inch out of the exhaust stream will kick the light into the off position. I just need to know if it is the upstream or downstream bung. Anybody got ideas? Thanks Terry.
Crap, it's on youtube, not prius chat. Oh well, at least I found what I was looking for. Hope this might help someone else.
You know what a 420 code in a Prius really is right? Prius is a hippie car so when you get the 420 code the car wants you to: Sorry, I just had to do it.