This 7 Days to Die mod makes cars (Sedans) in the color variants and 3 damage stages, bus variants and army trucks respawn randomly after disassembly (except by explosions).
The respawn block is an air block with no collision what avoids being accidentally broken.
Default respawning: 7 days.
In Readme has a tutorial to install the mod and to set a custom respawning days configuration.
The forum topic of the mod is here.