P0420 Code CEL and VSC Lights on

[oleblue]

So I just finished replacing my ABS module. Everything went well. I'm driving the 4 runner down the higway and the CEL comes on along with the VSC Trac/VSC Off.

So I pulled the codes and got 2 codes that were the same.
P0420 Catalyst System Effieciency Below Threshold (Bank 1)
I cleared the codes and they were back on within 10 miles.

I've searched and came to the conclusion the cats may be bad. Any work around for this that anyone has found other than a 02 sensor simulator?

Why would the VSC lights come on with the CEL? That is what makes me think there could be something else.

 

[sigepbiker]

The VSC Trac/VSC Off will always come on when the CEL comes on. That's how Toyota programmed it. Their reasoning: more lights, easier to notice something needs to be checked.

Sorry, can't help with the Cat problem. I had a P0420 code and ended up being the O2 sensors that needed to be replaced, so I would suggest starting cheap than starting with a $1300 bill for just the Cats and that's not the problem.

 

[CXS]

Check to see if you knocked an O2 cable loose. If not it's probably just a bad O2 sensor. IF they test out as good find a reputable muffler shop and have them cut the old one out and weld in a new one. Usually $300-$400 vs Toyota's $1300 rip-off.

 

[paperchasin]

Find someone with an OBD scanner that reads/outputs live data. This will help you pinpoint the P0420 code and determine whether its a faulty o2 sensor or you indeed and a bad catalytic converter.