Q&A

 Master

Here is the code information for P0170: Fuel Trim Malfunction (Bank #1).
Here is a previous question and answer about this code on another Mercedes: http://repairpal.com/p0170-fault-code-332
If you continue to drive with this issue, there is a possibility you can damage the catalytic converter, and those can get very expensive, so it's a bit of a gamble. If you have the option I say fix it first.