How do you change the air filter to a 1993 Toyota previa?

I haven't change my air filter in over a year in my Toyota previa. I used to get 330 miles on a full tank, now I'm only getting 280. I think it's the air filter.How do you change the air filter to a 1993 Toyota previa?It's under the hood on the far left. There is a big black box. Unclip the lid, and the air filter is inside. Replace and clip the lid back on. A couple of minurtes and you're done..How do you change the air filter to a 1993 Toyota previa?Purchase one at AutoZone and they'll gladly do it / show you how.