VSC LIGHT ON LS460L, 2008

[Jim Hamilton]

Lexus LS460,2008 VSC/engine/skid control lights keep coming  on. I have replaced the gas cap twice, new battery, cleaned battery posts and connections.

my mechanic said, their is no vacuum when you loosen the gas cap therefore there is a gas leak in the fuel system.  He said, I need a pressure gas tank test. Anyone have this issue  and know how to repair it ie besides the rip off dealer