I was riding with a friend once, that had a bit of contraband in his car, he got pulled over and before the cop could get out of his car he jumped out, pulled his pants down, cupped his junk and yelled, "IS THIS WHAT YOU'RE LOOKING FOR, OFFICER?!" He got a ticket for indecent exposure, and the car was never searched.
If the cop doesn't have probable cause to search your car then he can't do it without consent. No need for some indecent exposure stunt, all you have to say is "I'm sorry sir, but I don't consent to any searches" when a cop asks to look through your car.