I would first speak with your Mexican auto insurance carrier to see if they can cover your vehicle during your time in Texas.If they are unable to they might have a partner in the U.S. A partner might allow for a short term or temporary insurance policy because most insurance companies do not have this type of insurance available.

It might be possible for you to obtain a Texas auto insurance policy for a longer period of time than a week and then cancel. This again will depend on the guidelines of the insurance company you purchase the policy through. You can get a quote for Texas car insurance here.