Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_91 (driver VARCHAR, time_retired VARCHAR, grid VARCHAR)
### Question:
Who drive the car that retired due to engine failure and a grid of less than 9?
### Answer:
SELECT driver FROM table_name_91 WHERE time_retired = "engine" AND grid < 9