The quick answer is: yes. It will most likely hurt your credit to default on the auto title loan. Generally, missed payments on any loan or obligation that gets reported to the credit reporting agencies will negatively impact your credit rating.
If you are interested in how and why it will impact your credit score, read on...
First it is important to understand how your credit score is calculated. Your credit rating is calculated based on several variables, including: your payment history (do you have any late payments, charge-offs, etc.), the amount and type of debt that you owe, if you have maxed out any of your trade lines, and then several other secondary factors like the length of your credit history and how many recent inquiries have been made to look at your credit history.
Derogatory items remain on your credit report for up to 7 years. A bankruptcy may remain on your credit report for up to 10 years.