I realize that these scenarios stack the deck in an effort to lean you to one side....In this case it's the 'Snitch' one.
What kind of scenario would the DEA be involved in, finding some unspecified amount of cocaine in a vehicle, that isn't yours? Were you crossing an international border? Is your friend a drug trafficker, or transporter? Was he indicted? As far as amounts, if it was personal use, and someone talks, that is some weak shyt. If it's multiple ounces, your friend should step up and take it. If you are spending time with a person in that business, you should a) know his character, and b) have discussed this situation, and what your protocol is.
Here's some thoughts on 'snitching', limit your liabilities. Don't get involved in crimes for which you are unwilling to pay the price, if there is a serious risk of getting caught. Don't roll with cowards, or citizens, if there are liabilities. They will give you up. Leave them out of the equation. Don't involve people who are innocents or civilians in your affairs.
In all honesty, I've stood up multiple times in different situations...I remember in 04, I was 18, my homies and I got caught up, long story, but they found a gun that was tossed outside the car, by my boy. We were all charged with possession of a firearm, and other charges, related to personal items in our possession, including my switchblade. None of us talked. We went into county, and their parents/fam all bailed them out, one by one, until the last holding tank, and you change out, and I was all alone. I did 5 days, and went to court, all charges were dropped. You don't talk. But, that's just basic. You don't get points for NOT being a snitch.