Originally Posted by Retro
They will search your vehicle if they arrest you.
They can only search your vehicle with your consent prior to that or with a warrant.
They MAY search your vehicle anyway, but as long as you do not give consent, and better yet tell them that you do not consent to a search, if they find anything you shouldn't have your lawyer will file a motion to dismiss on Fourth Amendment grounds.
I suppose it depends on your jurisdiction, but in Florida for instance, a warrant is not
required. If the police develop probable cause, they can search.
Probable cause can come from seeing contraband in the vehicle, smelling the odor of narcotics, a K9 alert, finding dope on one of the occupants, etc.
They can no longer search the vehicle based on your arrest alone, AZ v Gant changed that.