About 20 million to 25 million Americans have no credit, according to the Fair Isaac Corp., the originator of the FICO credit score. Getting an auto loan, like all other loans, depends upon both credit score and your income. If you haven't used a lot of credit in the past, or have not used credit in a long time, you may have more difficulty obtaining a car loan because of your limited credit history. Credit History As a consumer, your interaction...