Blue smoke
 

After a 30min drive today i was sat at traffic lights for abit and looked in mirror and seen a cloud of blue smoke. It was only one and i might be being paranoid as it could of been of a passing car etc. I drove off from lights and nothing then after i got home i let it tick over few mins and still nothing. No smoke on cold start and not noticed anything before. Blob wrx decat and carrberry rom

check fluids if that's good and no smell just keep an eye on it hopfully it was some one else