2006 4Runner showing P0420 and C1201 codes

Hello all,

I’m new to owning a 4Runner. And was driving down the highway, notice check engine and VSC off and VSC Trac light went on.

Had the vehicle for about a month and it just threw a code on today showing P0420 and C1201.

I have read on some forums here saying it could be the O2 sensor or the entire cat itself. Need help with which way to go before I start paying for a new cat.

Thanks!

 

Best bet is to start with the O2 sensor. That will be the one after the cat, I believe, on the driver side. Go with OEM Toyota or Denso (which is OEM) and don't purchase one off Amazon as they are usually fakes and will not last long. You can get real Denso from rockauto.com. That should hopefully clear both of those codes. If not, then you can start thinking about replacing the exhaust manifold on the driver side since the cat is integrated with the manifold on either the V6 (I think) or the V8.

 

Thanks! It’s a SR5 V6. Is it still safe to drive with those codes on? I don’t want to further damage anything else.

 

P0420 is fine to drive on. The other code is most likely being caused by a failing O2 sensor as well, or it might be something else you find after. Either way, I wouldn't worry about it too much. O2 sensor runs like $40 to $70 ish, depending where you get it. Again, I recommend getting a Denso replacement from rockauto.

 

Thanks for the info! Hopefully I don’t have to shell out a ton for new cats.

 

Following same boat here. Will check these o2 sensors.