Im looking for the title of a movie which Im guessing was made in the late 1980’s.

American movie, action comedy

I dont have the names of the two actresses who played the mane roles but they werent popular or well known actresses.

Brunette lady cop, comfortable in tracsuit pants, has to protect a blonde rich spoilt girl. They start out bumping heads, the blonde washes her hair with dog shampoo, puts pantihose in the freezer and throws her underwear away instead of just adding it to laundry. The brunette cop needs to go undercover and she is seen wearing a coctail dress. The two eventually become friends.

That is all I can remember, please help me