Since January 1st, only diesel vehicles meeting the Euro 5 emissions standard are allowed into Stuttgart, home of Mercedes-Benz maker Daimler, Volkswagen subsidiary Porsche and the world's biggest car parts supplier Bosch.
The demonstrators held banners saying “Pro-diesel” and “Diesel drivers mobilise” as they gathered outside a car emissions centre.
“What's happening to people is unjust,” joint organiser Vasilos Topalis told AFP.
“Tens of thousands of people are affected and can't afford to buy a new car” following the court-ordered ban, he added.
Environmental organisations last year took to the courts to push through similar driving bans in many German cities where emissions exceed European Union limits.
Judges ordered Berlin, Mainz, Hamburg and Bonn to limit some diesels' access, while parts of a motorway near Essen will be closed to the cars.
In response, the Stuttgart organisers have asked people to hit the streets clad in the yellow high-visibility vests that have defined months of protests in France — themselves triggered by an increase in tax on diesel.
“Yellow vests give us visibility, also in the media,” Topalis said.
“The French are an example to us, because they dared take to the streets to protect their rights.”
Topalis was careful to delineate the movement from any existing political force, after far-right Alternative for Germany (AfD) attempted to capitalise on last week's demonstration that drew 1,200 people.
Increasing numbers have been drawn to the movement over its four weeks, as Germany's coalition government remains divided on how to balance the interests of drivers, city dwellers and the environment.