took my car to a shop recently just to see what codes came up, and what do know? I didnt write them down so bear with me...I got p0300, 400 maf circuit malfucntion, EGR fault or something like that, and bank 2 too lean. Now I know what 300 means but what about the rest? Can anyone breakdown what the last 3 codes mean???

 

Po 300 is random miss fires. Sounds like opti spark time????? Po 400 is EGR flow. and lean bank means that bank is running lean. Time to dig in and clear these codes one at a time. LOOK to clear up lean bank first. Vacuum leak ETC. Look at the fuel trim short and long and that will send you in the right direction