My mechanic tells me that the computer

Ok, If you have 2- 02 sensors, the front sensor does the primary fuel adjusments and the second one basically monitors the cat conv efficiency and trips the light. So the front, or #1 02 sensor shoul be changed also. E-proms to me are. "I don't know what is wrong" part that can never be found.The Mass air flow sensor will also adjust the fuel improperly if it is faulty or dirty. It is normally mounted in the intake ducting in a metal section. It measures the air density and volume and adjust the fuel to get the proper air fuel ratio. Sometimes, it can be in the air cleaner box. If you can locate itm it can be cleaned with CRCelectrical spray cleaner. Do not touch, rub, or brush this very sensitive sensor. The cleaner will dry on its own so no compressed air should be used. They are the most expensive sensor to replace. No need to remove it from the mounting either. Chk the connections first. Ensure it is clean and firmly plug in. Good Luck, Ned

You may have to get a whole computer out of a junk yard,and hope the prom will work,and on that car,it should.