how do i get to the thermostat on a 98 buick century

You will need to obtain a 13 mm"S" wrench. Once obtained, remove the air filter box cover and filter, and the hose connecting it to the throttle body. Use the wrench to remove the top bolt on the thermostat housing, then loosen the bottom bolt, but don't remove it. The housing should then slide off the loosened bottom bolt in an upward motion.

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