Hello,I will be glad to try and assist you with this,Welcome to Just Answer.
codes 300,301,302 and 304 are all misfire codes meaning that the engine is misfiring and the computer is picking up the misfire.
Code 103 is a mass airflow sensor code,this code can cause the other codes to set and the misfire.
I would check your mass airflow sensor and even your air filter assembly,if a nest or debris has built up in the air filter box then this would restrict the air,and cause a misfire and these codes.
If no debris or anything is found clogging the air filter assembly then I would remove and try and clean the mass airflow sensor to see if this doesn't correct the problem here.The mass airflow will be either located in line with your air inlet into the engine or on top of the throttle body.
But since this sat for 2 years there could be a good chance a nest or debris has built up in the air cleaner and air cleaner box.Let me know if you need anything else,Thanks Pete!