Scanned a 2003 Mitsubishi Lancer non turbo that had a check engine light. When scanned with Generic OBDII it shows the P0403 EGR code that the customer was told it had by autozone. When I switched to scan it again using the Mitsubishi manufacturer specific option it showed no codes and all modules pass.
I have always thought that the manufacturer specific would be the way to go but now I am reluctant about even using the specific option.