C180k grinding cold start and high idle speed..?

[best]

When cold starting my '03 C180k Automatic I hear a grinding noise for about 4-5 seconds then it goes away.. and this afternoon I noticed a high idle speed - > 1250rpm.. are these related? I fearful something is about to go.. any checks I can do before I bring to MB Rip off?

 

[best]

Appears the cold start grinding noise was the early indicator of a timing chain problem that needed attention.. we live and learn!

 

[tolly]

might be the starting motor getting stuck after start and about the high idle, check you MAF sensor