Engine Performance problem
2002 Ford Escort 4 cyl Two Wheel Drive Automatic 95k miles
My " service engine soon" light came on and stayed on. I had a major auto parts chain diagnose it, and they informed me the code was for replacing the mass air flow sensor. Where is this located, and how can I be certain this is the problem? Also, how will this affect the performance of my car? I am still using the car, and I haven't noticed any difference in the way it runs.