Although it works quite well making coal into liquid gasoline to run automobiles, you can also use coal as a solid to run cars.
This was done in Stanley Steamers as well as in the gunpowder motors of the 1910’s that used gravity to draw gunpowder into a combustion chamber.
Well, coal (even in solid form) can likewise be directly used for combustion.
The original DIESEL engines ran on COAL DUST!.............