You're bombarded with letters for pre-approved credit cards and you've never missed a credit card payment. You assume you have perfect credit. Erica Sanberg, Chief Financial Writer for Consumer Credit Counseling Service of San Francisco, says don't be so sure. Making payments on time is only part of what creditors look at in determining your credit score. They also look at what is owed, your available credit limits, and how long you've had credit. If you want to know your real credit status before applying for a car loan or mortgage, go to www.myfico.com. For $12.95, you will get your credit report and FICO score, along with detailed explanations.