My wife drives a 2000 430E which she let me in a couple of weeks ago(lol). While idleing with brake on, like at a stoplight, especially when cold, there is a distinct vibration I can feel through steering wheel. I thought it probably was related to the harmonic balancer problem, but I finally got MB's letter and had it replaced a few days ago but the vibration is still there. Any suggestions of what to check next? 120k miles and had all the A & B service done on schedule through 100k.