Certainly, never while driving. Maybe things got things heated up within the car, but I don't ever recall completing the sexual act in the car. Always ended up someplace other than the car (into comfort, not being folded like a pretzel).
I was involved in an accident once where a couple was "playing" with each other while driving. Traffic came to a stop on Interstate 10 on a nice, sunny day in Beaumont, Texas. I was sitting there at the very back of this line of stopped traffic. A Ford pick up truck slammed into the back of the Camero I was driving at 65 miles per hour. A very bad feeling knowing I was about to be hit at full speed. At the very last moment the guy driving tugged the steering wheel to the left so that the impact was only on the left half of the rear of the car. He never hit the brakes.
The rear fastback glass exploded as the truck folded the left rear side of the car towards me in the drivers seat. Other than the sound of the impact, there wasn't much to remember. I was unaware of how much force was applied to me as my car was driven forward. A moment later I became aware of the truck passing by my left shoulder as it bounced into the center (Jersey barricade) retaining wall. The truck bounced off the center wall and before the front of my car could slide into the car in front of me, the truck hit the car in front of me (driving his car into the car in front of him). The truck bounced off and back to the left into the center wall where it slid to a stop, engine still running at high speed. The right rear wheel was off the pavement and the truck didn't have a limited slip differential.
I managed to open my driver's side door and unbuckle my seat belt. I was covered in the tiny shards of safety glass that had exploded into the passenger compartment on impact. I walked up to the two vehicles in front of me and those drivers were okay. When I walked up to the truck, I wasn't sure what I would find. The right door was unlocked and I was able to open it. The couple in the bench style seat of the truck were slid over towards the left side of the truck, stunned, a bit undressed from their little sexual escapade but otherwise apparently unhurt. I reached in and turned off the ignition. I asked them if they were hurt and they indicated that they didn't think so. I said something about them getting dressed before they got out of the truck but left it at that.
After calling 911, I waited for the police to show up. The couple in the truck eventually got themselves back into a state of being dressed and got out of the truck, In retrospect, I probably should have gone to the hospital to be checked out. No whiplash apparent as the high-back seats of the Camero did their job. But I really had a great deal of muscle soreness over then next couple of days while I was working at a job site in Louisiana.
The force of impact was so great that the pair of Ray Ban shooter style glasses (with the sports safety bar above the bridge of my nose) cut me above my left eye when my face was accelerated into them (the metal frame) on impact. I was initially unaware that I was bleeding a trickle of blood down the left side of my nose.
Oh, the car I was driving was completely totaled. The frame was twisted and bent from the impact. The fact that the gas tank was above the differential in that model year provided enough protection from the gas tank being ruptured. I was picking glass out of luggage and my my clothing for days after the impact.
I was quite lucky to walk away. As a victim of "distracted driving" from a couple who was equally lucky to walk away, I wasn't ever tempted again to consider it.