Would you allow a cop to search your car without a warrant?

[HAnnA MArin County]

I've only been pulled over once where he asked to search my car, and I said yes. Here's what happened:

It was late one night/early morning and I was, um, visiting a friend. Well, as I walking out and getting into my car from friend's house, a cop drove by. He slowed down and saw me getting into my car, and I was leaving town, sirens went on. He pulled me over and asked what I was doing out so late and I said I was visiting a friend. Gave him my license and proof of insurance, and he asked if he went to the friend's house and asked if I was there if the friend would say I was (?) and I said, well yeah, and he let me go. So as I was leaving town again, about five minutes later, he pulled me over again and said that the friend said I wasn't there, and then he asked if I was on drugs or if I had drugs in my car and I said no, and he asked to search my vehicle, and I said okay because I had nothing to hide. So he searched and found nothing, he apologized and was just "wondering" why I was there so late (I was about an hour away from home). I told him he probably didn't want to know but that I could assure him that I was not doing anything illegal, and with that, I finally left Malden.