There have been a lot of car companies since the invention of the automobile but few have made it through their start up years.
In the early years of the automobile, there were very few players. For example Edsel Ford did the artistry for Lincoln founded by Henry Leland who was former manager at Cadillac. Well another example of this is the Flanders Motor Company started in 1910 that was founded by a Ford plant manager, Walter Flanders. In 1912 Flanders needed help from the Studebaker brothers to outsell the Model T and soon the Flanders Motor Company was absorbed into Studebaker which merged with Packard. Kaiser, Auburn, and Pegaso have similar stories of mergers and takeovers to make for a long lifetime but here are some that just disappeared.
Delorean is a famous ex-car manufacturer. With a 7 year stint from 1975-1982 some say the car was too futuristic, either way the company went bankrupt but all the excess parts are stilling being sold today.
Tucker is another one, because a film was made about this manufacturer. Preston tucker hand built a car in 1946, was an amazing salesman and got a plant to manufacturer his car. However only 51 cars, handbuilt were ever made by Tucker. He had no mind for production, could not reconcile how to get his car to be built on a manufacturing line and as his parts failed, so did the company in 1948.
Voisin was strictly a French aviation company until it started making cars in 1919 and lasted until 1946. Do not despair, the designer for Voisin got hired by Renault which still remains and then by Citroen, also still alive.
Italian company Siata modified cars but started manufacturing them from 1948 to bankruptcy in 1970. Limited productions of these road racings cars were made and Steve McQueen owned one.
Simplex Motor car company produced cars from 1906-1915. Before Cadillac, the American Simplex had a self-starting car. Similarly named Crane-Simplex was short lived but bought out by Mercer which produced its last vehicle in 1925 but the company has not yet been dissolved.
Iso Rivolta which made the famous Isetta and the Grifo started with motorcycles and scooters. Its first car was made in 1953, the tiny Isetta which was licensed to other manufacturers, like BMW. It was in 1974 the company went bankrupt.
Pierce-Arrow lasted from 1901-1938. Failure to have an economy car in its line-up is surmised to be the downfall of this company.
Pope-Toledo was from 1903-1915. This company pioneered the interchangeable part but somehow was not able to compete with other manufacturers.