I have a P0300 random misfire that is robbing power and wasting lots of gas.
When I am idling my engine light stays on solid. As I drive the RPM's go up and up until i let off the gas but the light stays solid. As soon as the transmision shifts to the next gear, the light flashes and stays flashing until i come to a stop and then it is solid again. Any ideas what is causing the problem? i originally thought it was a bad coil but when i replaced it it wouldn't even start up the car. I put a diffrent brand new coil on it but the same result. I put my old one back on and it starts up but runs and idles rough with no power at all.