Which is the first diesel car launched ??
The first diesel passenger car that was introduced for the market was Mercedes-Benz 260 D in the 1936's Berlin Motor Show. But the model was not successful due to dimension and weight of the diesel engine.
However the first ever diesel engine was invented by Rudolf Diesel in 1893 which ran on biofuel (peanut oil to be exact) and he obtained the patent for it in 1898