I have a '98 E320 with an electronic key. I have been experiencing starting problems. Initially the problems were very occasional but now they have become more frequent. Teh car tries to start cranks once and the freezes. If I remove the key and try again it usually kicks right over. Most recently, on a couple of occasions, the car kept cranking. I turned it off and restarted it without a problem. The battery is only 6 months old. Is this a starter problem or a solenoid problem? Any help will be appreciated. Thanks.

Dan