Louis de Funès had had a heart attack one year earlier and this marked his return to movies. The ads were supposed to have only his name above the title with Coluche's name in the lower credits. It was de Funès himself who insisted that the posters should announce "De Funès et Coluche" above the title.
The service area shown in the lead credits is the "Aire de Nemours" at motorway A6, direction Lyon, about 80 kilometers southeast of Paris (km 74).
According to Claude Zidi, the character Tricatel was inspired by Jacques Borel, a French industrialist who in the 1960s had the concession for roadhouses at French highways.
In an interview, Zidi said that he made a mistake at the end in the scene where de Funès analyses the wine. Prior to that scene, since Tricatel knew that de Funès had lost his sense of taste, instead of being angry by de Funès sudden participation, Tricatel should have been elated that de Funès decided to participate.
A soundtrack is entitled "Agnosie" although it is question about agueusia (agueusie in French) by the last third of the movie (so, word misspelled because only mentioned in a phone call during pre-production??)