P0300 2008 Pontiac grand prix 3.8v6

Question

ive had problems with engine hesitation and and when idling
had them check my codes and P0300 came up i just ordered an ignition module and a new ignition coil since im running opn 4 cylinders instead of my full 6.... hoping this is the cause

Answer 1

have you replaced spark plugs? if you ordered ignition module and a new ignition coil thats a start 

If you use low octane fuel, I would suggest you use 91 octane from shell and use a good fuel system cleaner