if you have separated parts Props it is the best way to start up rigging a car as it has no bending parts. start assembling the parts in Poser. creating a logical Prop hierarchy, make sure to use the Hierarchy editor to do it by drag and drop the props until you get a good tree. it is the basic of figure creation !! the moment you have the Props in a good Hierarchy mark the main top part that holds all parts together in the editor.

On the bottom right of the editor you will see the option to create a New figure. Click this option and it will save it as figure in poser the path will be in the root New figures of Poser.

Make sure that every Prop has no spaces in there naming else it will not work properly ( Left Door ) must be named LeftDoor. if you have spaces it could cause to lose parts when saving the geometry later on.

you now will find a new figure in the New folder it is boned , and Grouped. Load this new Figure you made and before you work on it save it again in your Librarie as new figure were you want to work with , this stepp is important as it will generate the External geometry file.

now you all ready to rigg your Car. open this file then check every body part disabling Bend in the properties of the bodypart , an important part as a car has no bending parts. when done you will have to start to use the Joint editor found in the Window options of Poser.

When the joint editor is open you can select the bodypart you want to adjust. you will see two lines a red and green one. you have to position the green cross where you want the bending to be. the red cross is not important as you have no bending. use the front and side view to get an exact position of the green center. for a wheel the green cross is in the Center back of the wheel for correct bending and spinning. do this foe every bodypart that will need a correct movement . make also sure that the angle of the green axis fits to the rotations position as the bone is always zero.

by trying these simple starting steps you will slowly get into the things as you will try the options and learn fast. it will not work the first time so just try over and over again until you are content with the results.

most tutorials are complicated using the Setup room witch is not really the place to start off with boning as Poser does automatically in the Hierarchy editor so try it this way and I am sure you will get fast into things.