2002 Pontiac Grand Am

Engine Performance problem
2002 Pontiac Grand Am 6 cyl Front Wheel Drive Automatic 123000 miles

I have a 2002 pontiac grand am GT I keep getting a code P0300 for ramdaom cylinder misfire. I was wanting and answer as to what would cause that we changed the spark plugs and the wires and about to change the transmission fluid because it needs it but what else could cause a cylinder misfire?
August 22, 2009.

P0300 Random misfires normally caused by vacuum leaks and bad fuel

Engine misfiring can be caused by worn or fouled spark plugs, a weak spark (weak coil, bad spark plug wire), loss of compression, vacuum leaks, anything that causes an unusually lean fuel mixture (lean misfire), an EGR valve that is stuck open, dirty fuel injectors, low fuel pressure, or even bad fuel

Aug 22, 2009.