I would probably refuse to give consent for a search, unless they had a warrant or could articulate probable cause to search my vehicle.
I guess I could "be a chump" about it, and give them consent, but not as long as innocent Americans continue to be harassed and persecuted by their own government (the latest example is the guy in LA who got arrested for making holsters, although there are thousands of others of cases).
“Necessity is the plea of every infringement of human freedom. It is the argument of tyrants; it is the creed of slaves.” – William Pitt