Hi, I had a similar problem with my 1996 BMW 328I. You might want to check several different things; starter, starter solenoid, ignition wires, spark plugs, ignition control unit, ignition switch. In my case it was the starter that had to be replaced, buy ive found bmw's to give a hard time when dealing with starting issues. for some reason mechanics have a hard time finding out what the problem realy is, but hopefully with this list youll be able to narrow it down fast. I actually got the starter at an online store (qeautoparts.com) which has live assistance, so if you have any questions while browsing through their catalogue you can get help right away, anyways, this store got me a great deal on the starter. hope this helps and good luck. let me know how it turns out.