Help, X5 multiple misfire codes. Stumped

[craigndee]

Hi guys. 2003 BMW X5 4.4, idles rough at start up, smoothes out when warmer. Got a check engine light on with three codes. P0363 Misfire detected fueling disabled, P1343 and p1351 Manufacturer ctrol ignition sys or misfire,. Strange thing is when warm it seems to drive ok, but when under hard acceleration the Check engine light flashes for the misfire which can then be felt a little. Keep driving and the light stops flashing and stays on. Hit the gas hard again and it starts flashing again. Ruled out the MAF, idle changes to much when unplugged. Does not seem to have a vacuum on the oil cap. Changed the coil on cyl 5 to no avail. Possible cam sensor? My reader gives only those three codes and does not read a cam sensor error. Could a bad cat be backing up the system at high RPM's? Any thoughts would be greatly appreciated!