I have a 2010 R350 4Matic gas with two problems. First, under hard acceleration there is a clicking sound coming from the front left wheel sometimes it will also happen when taking tight turns. Looking under it everything seems normal the CV boots are not cracked and otherwise the car drives fine. Second I can turn the key to position 3 but it will not respond eventually it will respond and run fine the key battery has been replaced and battery is fine. What could be the causes?

I just looked and found that the FL inner wall is worn down to the belts. Could that be the cause?