Unfortunately, all contributions (other than rollovers) to IRAs must be in cash. Property cannot be contributed as a contribution.
See explanations on page 7 under Individual Retirement Account - http://www.irs.gov/pub/irs-pdf/p590.pdf
Unfortunately, that cannot be done either because it would be considered a prohibited transaction and make the entire IRA immediately subject to income taxes. A prohibited transaction would occur when property is sold or exchanged between the IRA owner and the IRA account.
The IRS would still probably consider that a prohibited transaction since the IRA which owns 100% of the LLC is acquiring the car directly from you. An IRA can be the owner of a business and avoid prohibited transactions if done properly. However, if you sell property to a business that the IRA owns more than 50% of then a prohibited transaction will occur.