Only has fire to Right bank plugs and nothing on left side. have put on new timing belt, plugs and PCM OBD-ll code PO300

By "only has fire", do you mean spark? If so, check the coil/coils (I can't remember if it is a coil-on-plug engine or not). If it has spark and fuel and just not firing, check compression. Perhaps you have a bad head gasket. Hard to tell not being there.

Has the ignition module 'circuits' been checked?