Nope. I'm right in response to Rastoff saying police can not search without probable cause. That's basic search and seizure stuff. Google "Motor Vehicle Exception to Search Warrant Rule". It will give you all the case law. You have a right to say "no" to ANYthing the cops ask. If they have probable cause to believe you have evidence of a crime or contraband, or reasonable suspicions to believe you're armed and potentially dangerous, they're going to search, and they can do it without a warrant. Recently the Supreme Court HAS reigned in the government as far as the scope of where they can search incident to arrest in AZ. V Gant (I think that was it), but there are still various exceptions to the search warrant rule such as Motor Vehicle/Exigent Circumstances. No warrant needed for a motor vehicle on the road as long as there's probable cause for evidence or contraband or reasonable suspicion for weapons.

Another example, if someone calls the cops as says: "My name is John Doe and my number is 234-4565 and the guy in line at the DWI checkpoint in Green Chevy with the dent in the left door has a bail of marijuana in the trunk", that's probable cause for a warrantless search.

Oh, also, the cops don't need a reason to compel you to get out of the car on a valid traffic stop either. A lot of people talk themselves into an arrest and a search by refusing to get out of the car. "Step out of the car sir." "Huh? No, you can't make me get out of the car." "OK, you're under arrest for refusing to comply with a lawful order." Then we search them incident to arrest and do an inventory search of their car and may or may not arrest them.