I'm guessing for your car since it's a 97...
Basically, the MAS (mass air sensor, or air flow meter) reads the intake air volume and density and sends information to adjust fuel mixture to accomodate the changes. In the old days, your carburetor choke did this during warmups...needless to say, this unit came about with fuel injected components and computer management systems.
The MAS is housed in a black plastic cylindrical chamber (about the size of a small coffee can), and resides between the air cleaner housing and the intake manifold...it is usually directly behind the air cleaner. There should be a wire harness attached to the side of the chamber where the sensors electrical posts are attached.
Removal and installation should be fairly simple...it may require removal of the air cleaner assembly for easier access, but the operation can be done without tools. Clips hold everything in place, so maybe a screwdriver is needed to aid in popping the clips open.
Again, I've done mine, but I have a 93, so your configuration is probably different...
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