Even though I don't keep contraband or weapons in my car, I never give the police permission to search my vehicle. However, if the police want to search your car they will. I had an incident where I was stopped and the police asked to search my car. I said no (I was under 21 and had beer in my car). The cop made up a BS excuse and searched my car anyway. When I went to court the charges were dropped due to illegal search and seizure.

To search a vehicle the police technically need probabale cause, however there are some technicalities If the police have reasonable suspicion they can hold for a reasonable amount of time for a drug dog to do a quick sweep around the car. If the dog detects nothing, you are free to go. Should the dog bark they can search your car and they can charge you with anything they find in the car. A good lawyer should be able to get you out of any charges should that happen.

As far as a ticket for intake, I've never heard of such a thing. Unless it violates emissions law, you should not have recieved a ticket for an intake. The cops cannot make up laws as they see fit. I would ask the cop to show me in the code of VA where it says intakes are illegal.