2004 Toyota sequoia 225k SR4 4x4

[Cue]

hi sequoia fans. i own the subject toyota which is maintained well. i ran into a yellow light today and seeking some information and guidence.
i was driving earlier in the day in 4x4 for few miles in messy snow road and it was no issues.
i then had 4x4 off and drove fine and then after a few miles, the check engine + VSC off + VSC TRAC ( all 3 ) lights came on.
as far as driving was concerned, drove fine no issues that i could feel diff in performance.

i did some research and found everything from gas tank cap, yaw sensor and 0 possible calibration issue?
i checked gas cap and appears tight and closed well. last work was oil change performed 8 weeks back.

i checked with scan tool which gave me a P0420/P0430, two codes with info,
"Catalyst System Efficiency Below Threshold Bank 1" + "Catalyst System Efficiency Below Threshold Bank 2"

i followed some steps, to clear the code, and it went away, and put vehicle in N, turned off and on and two VSC lights went off.
two weeks later, the same set of lights are back on. where do i start?

 

[CBStine]

This just happened to me too. Did you ever figure out the cause?

 

[JPav]

Could be a number of things, but I've gotten those codes due to a exhaust leak.

 

[Sequoia03]

This is my problem as well. I found out that I had a small hole in my exhaust pipe and so the evap system was freaking out. Every time I reset the check engine light it stays off for a while but as soon as I accelerate remotely hard, then it turns right back on. It doesn’t seem to affect the performance of the vehicle though. If anything, it just decreases the mpg a little bit, but otherwise it’ll run just fine. It is annoying having all those lights on though.