This morning (before heading off to work), I tried two tests to see if I could determine what was causing my multiple misfire codes for only one side of the engine.

1st) I took out the O2 sensor (before the catalytic convertor) and drove it without the O2 sensor to see if the catalytic convertor was bad. The X5 was still running rough and throwing the same codes. This must mean the catalytic convertor is working. if the rough idling issue had stopped, that would of meant the catalytic convertor was clogged and bad.

2nd) after putting the O2 sensor back in, I started the X5 and while it was running I removed the plug from each ignition coil (one at a time), to see if the idling of the engine would change. The engine idle didn't change. I believe the idle should of changed if the ignition coils were firing. So that must mean the coils are not firing as the codes suggest.

Tonight I will remove each ignition coil (one at a time) and the corresponding spark plug, keep the ignition coil connected to the power plug and have the spark plug connected to it as well. I will then have someone turn the igition on as I hold the threading part of the spark plug next to a good ground (-) on the car with the expected results being my ability to see the spark generate on the spark plug. If I don't see a spark, that would mean there is no fire going to the spark plug, which MAY mean the iginition coil isn't working.

Any advice?

One last thing, I sprayed my MAF sensor with MAF sensor cleaner and now it doesn't work. So now I have to order a new one.