2004 toyota sienna engine and vsc light

well the check engine light on can mean many different issues its just a symbol telling you that your ecu (engine computer) has found an issue with your vehicle it is not a specific indicator of whats going on unless you get the codes pulled from your computer any autozone will pull the codes for free and some shops will also just call around they will not diagnose prob for free though it could be anything vacume leaks - o2 sensor bad ext....as far as your vsc being on most of the time when your check engine light comes on the vsc will light up also does not mean there is an issue with your vsc system....i work as a mechanic for a toyota dealer and see his all the time and check to make sure your gas cap is tight will set check eng and i see it all the time when custs forget to tighhten gas cap if its loose you can get the codes erased hope this helps!!!!