a strong gas smell in the cabin of my 2012 buick lacrosse

White smoke can indeed be a result of excessive fuel delivery - however this normally causes engine performance issues and check engine light to be illuminated. Steam from exhaust can easily be mistaken for while smoke upon cold engine start up in cold ambient temperatures. The only way to positively identify this problem is to have qualified personnel perform *hands-on* inspection & testing so the culprit can be determined.