Mitsubishi Repair: computer error codes 1992 Mitsubishi Eclipse 2.0 non-turbo, mass air flow sensor, mass air flow

Question
Replaced the mass airflow sensor with a used one. The performance has improved 95%, yet the computer error msg still says barametric presure sensor error and mass air flow sensor error. the harness visually appears fine, and the performance is a majot improvement. do i need to unplug the battery terminal more than 20 minutes to reset the computer?

Answer
20 minutes should easily reset the codes, although I usually remove both cables and then touch them together (and then clean the terminals) and hold for 30 seconds or so to help the capacitors in the computer discharge fully. Does this light come on instantly after switching the key on? Have you done any modifications such as going to a 2G MAF and wiring changes?

Try the battery trick and if that doesn't work, follow up tomorrow on how long it takes for the check engine light to illuminate.