BMW Repair: 99 528 smoke smell after changing plugs, valve cover gasket, vanity mirror

Question
Hi nathan,  I asked you question about my '99 528i wagon like 2 days ago.  it was regarding a power drop...you suggested it might be the ignition switch and to mess with the vanity mirror.  the problem has not reoccurred, so i have not had a chance to try your solution.  i did mess with the vanity mirror when the car was acting normal and nothing happened.  

I have another issue which started at the same time that i changed the plugs.  I don't know if the two problems are connected but i assumed so.  after changing the plugs i drove the car to test to see if the miss fire was gone and i noticed a bit of a burning smell which was not there before changing the plugs.  I immediately pulled over and popped the hood.  there was a little bit of white smoke in the engine compartment but i didn't pin point its origin.  i was right next door to the bmw dealer so i asked them what they thought it was.  they thought i just had some crud that needed to be burned out of the spark plug compartment.  they told me as i drove it it should get better.  it did and i no longer see any smoke but i still smell the burning smell from time to time...i think it smells like electrical burning...not 100%.  

one of the coil to spark plug tubes had a small tear in it so i replaced it yesterday, took it for a drive and still smelled the burning.  i popped the hood and tried to locate the source but couldn't smell anything under the hood only inside the car...and only if i'm stopped.    could this be coming from the ignition coil you suggested might be bad or do you think it might be something else?  if i connect a code reader, will it tell me if the ignition switch is bad?

Answer
It sounds like maybe the valve cover gasket is leaking oil on the exhaust manifold causing the smell, the exhaust manifold burns the oil up, smokes and makes a odor but never leaks on the ground because it burns up before it can make it onto the ground where you can see a leak.   Hope this helps    Thanks Nathan