It may be located behind your glove box. You should see a thin panel type plastic piece. that would be your filter. Careful when you pull it out so you don't get sand and leaves inside the blower motor housing.
The 1999 Nissan Maxima does not have a cabin air filter. It never came with one.
Yes, it has a filter. Click the link for instructions.
Behind the glove box
2000 Nissan xterra cabin air filter
is there a cabin air filter on 1997 maxima
take of glove compartment then you see the cabin filter
Filters for a Nissan Maxima need to be changed every 15,000 miles. To change it remove the screws, release the retaining clips, and remove the glove box bulb.
in glove box
where is cabin filter
The cabin filter was introduced to Nissan Frontier's in 2002.
I doubt that a 1993 model has a cabin filter. Go to a parts store and ask for one. If it has one they will sell it to you. Purolator cabin filters come with instructions.
The cabin air filter is located behind the glove compartment, you will have to unscrew 7 screws to remove it and to get access to the Cabin Micro-filters door. Nissan recommends to replace the micro-filters every year or every 15,000 miles.