What type of freon is used in 1997 corolla?
It depends on the year of the car. From 1994 on, R134a refrigerant is used. Prior to that, they used R12 refrigerant (Freon). R134a is technically not "Freon". Be alert, however, as many older cars (like my 1986 Camry) have been retro-fitted with R134a systems, and can no longer accept Freon, as the two refrigerants are not compatible.
Source: wikipedia as a 'freon wiki' search in Google (0.08 seconds) Freon is DuPont's trade name for its odorless, colorless, nonflammable, and noncorrosive chlorofluorocarbon and hydrochlorofluorocarbon refrigerants, which are used in air conditioning and refrigeration systems. Freon was initially developed in the early 20th century as an alternative to the toxic gases that were previously used as refrigerants, such as ammonia, chloromethane, and sulfur dioxide. Freon, in this case dichlorodifluoromethane, was invented by Thomas Midgley…
R-22 (Freon 22) is used in a lot of home air conditioners. In the mid-1990s, manufacturers started switching to R-134a refrigerant. The manufacturers' data plate on the unit provides information about what type of refrigerant is used in a given installation. Manufacture of Freon 22 is being phased out and it is extremely expensive.