The video shows the blue car hogging the middle lane of the AP-6 motorway near Villcastin, Segovia, as the woman, who is naked from the waist up, bounces up and down on the man's lap.
The man and woman have been tracked down by police and on suspicion of reckless driving.
The man faces being banned from the roads for up to two years and fined £440 if found guilty by a court.
The man was forced to reveal the identity of his lover by police who have not revealed the identity of the pair.
The only details of the male driver that have been released is that he is from the Madrid area.
A spokesman for the Civil Guard confirmed: 'Police became aware of a video circulating on social media in which the driver of a car could be seen having s-x with his passenger.
'It was a video lasting 32 seconds and the car could be seen in the middle lane. The motorway it was travelling on was identified as the AP-6.
'After viewing several hours of traffic cameras the car was identified and the identify of the driver confirmed. He lives in the province of Madrid.
'When he was told why he was under investigation, he confessed and identified the woman with him, who was also being probed on suspicion of reckless driving.
'This behaviour is punishable by up to two years in prison and a 500 Euro fine.'