Nope, a cops "hunch" is never probable cause. Neither is him claiming to smell something funny. Only probable cause is if something is in plain view, like roaches in an ash tray, a mysterious bag with green stuff on the back seat, etc. Then, he can check out whatever he sees, and if that roach in the ashtray is weed, he can proceed to search the car.

Its really not hard to avoid getting busted...people just don't know their rights or are too scared to excercise them. Cops intimidate people to think otherwise, seriously, everyone watch that video, as long as you hide your stash, you are pretty much safe.