the car, open hood, look and under see sticker there and shows idle speed there, for sure, if USA car , it does by EPA law the sticker.
see 1990 here
https://fixkick.com/specs/Body-TAGS/html/image_2.html
see 1990 here
https://fixkick.com/specs/Body-TAGS/html/image_2.html
http://www.fixkick.com