Final answer:
A temporary substitute vehicle is not covered under an auto insurance policy if used to substitute for a rental car according to most standard personal automobile policies.
Step-by-step explanation:
In most cases a temporary substitute vehicle is covered under an automobile insurance when you cannot use your regularly insured car because of its breakdown, repair, services, etc. However, there is a limitation on which cars can be substituted. According to the standard personal automobile policy, a temporary substitute vehicle is not considered a covered auto when it is being used to substitute for a rental car. This includes when your regular car is unavailable because you've loaned it to someone else, and you're using a rental vehicle as a temporary replacement.
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