4 Wheel Drive/SUVs: engine light warning, toyota 4runner, oxygen sensors

Question
I have a 2003 toyota four runner. My check engine soon light came on along with two seperate lights which say VSC trac and VSC on

Answer
This I have never heard of before, but i did a little reasearch online and found out that you are not alone.
At http://www.toyota-4runner.org/showthread.php?s=cfe5e0566c905f14ebcd95acc46bfde9&...
I found the following excerpt "4Runner has 4 Oxygen sensors (1 on either side of each Cat). Engine side sensor monitors "dirty air", muffler side sensor monitors "clean air". If either sensor (or either side) fails, it throws the CEL. Makes sense to this point, right? On 2004+ models (and if you had the Sulfur TSB), if the CEL(check engine light) is lit, it also DISABLES the VSC/TRAC systems."

I have also read that if your gas cap was not on tight, that the CEL would light up, and when the PCM lights the CEL it disables the VSC Trac, and Trac to lighten the load on the engine. Id check to make sure your gas cap is tightend at least 3 clicks, then see what happens, if the lights still dont go off take it to the dealership where you got it and tell them whats going on.