Obdll problem for code 301

I have 2004 chevy impala.The engine light comes on .I checked it and it gave me code 301.I change spark plug and wires but the engine light is still on. And I also changed the coil number one.When I turn off the engine light manuly it comes back in about 30 milles and during the time that engine light is off the car runs good but when the engine light comes on the car does not run good.What do you suggest? what is wrong with my car?

It’s time to work on the fuel system (fuel to, and fuel injection into, the engine).
If you haven’t changed the fuel filter…hint!..hint!
Then, “call” us back.