Toledo Motor Failure 99 1.6 AKL Gasoline

Hi everyone, I have a 1999 Toledo 1.6 petrol with an AKL engine. I hooked it up to a diagnostic tool and the code it came up with is 00668 terminal +30. When I go into the engine information, it's not reading the mass airflow sensor, lambda sensor, throttle position sensor, lambda resistance sensor, etc., correctly. I replaced the engine relay and the temperature sensor because they weren't working sometimes either. It's running a little better, but not perfectly. Has anyone else encountered this problem? Any help would be greatly appreciated. Thanks, and greetings.

Look in the fuse zone and locate the terminal 30 that has a nut, see that it is lazy because the cable is fine but if the nut is already lazy and small current cuts.