Hey guys this is the first time posting on this forum so sorry if im in the wrong place. Im posting this for a buddy of mine, I hooked my obd scanner up to his truck today and it gave me the random multiple cylinder missfire code today, We also popped the hood and heard a slight knock every few seconds. He says the carb is pouring in more gas than needed also. Could that be why its missfiring and knocking? Sorry were both only 16 and dont know everything, I myself know more about fuel injected. Any help is appreciated.