2002 Suifire P0300 misfire

Hello all my GFs car wouldnt start one day so i pulled the codes off it changed the plugs and replaced the ignition coil she been driving and the CEL P0300 came back again signaling another misfire any other possible solutions?

Thanks for any help

check the TPS(throttle position sensor) if it is bad then it will said a bad reading to the computer causing it to shoot the code multiple/random misfire by not giving enough gas or giving too much gas into the cylinders.

Did you install Bosch plat plugs?