While not actual sex in a car, one of my favorite memories is taking my girl friend with me to my home state to visit my extended family for Christmas.
It was the first time I had brought a girl friend to meet all my family and the first time she had traveled out of state with a boyfriend.
We spent the long weekend staying with my grandparents and aunts, uncles, and cousins were coming and going all weekend. We certainly did not sleep together, even sleeping in separate rooms. There was also no where to be alone for more than a few minutes, so we only held hands and occasionally kissed during the whole weekend. We both wanted our hands on each other .
By the time we were making our drive back home, we were both horny and longing for some intimate touch.
It was dusk as we got out of the city and on the open highway. I reached over to unbutton and unzip her jeans. My fingers slid smoothly down her flat tummy and into the waist band of her panties. I let my fingers glide through her pubic bush until my hand was cupped over the mound of her sweet pussy.
Within moments I felt her wetness and my middle finger slipped between the slit of her juicy cunt to nestle inside her where we both wanted it to be.
She leaned her head over on my arm as she placed her right hand on my arm also.
I looked over at her and she was looking at me dreamily and smiling. I continued fingering her pussy, making circles and stroking in and out, while the heel of my palm was rubbing on her clit.
I fingered her most of the drive back home and kept her on the edge, before finally having her cum.
That was a trip I will never forget and I think she won't either.
We did eventually have sex in a car, after we were engaged to be married. That is a story for another time perhaps.