Air cabin filter

No info for 2011 but a 2008 has a filter same model E350 could be there

REMOVAL & INSTALLATION
NOTE:Manufacturer's terminology for this filter is activated charcoal filter, dust filter or HVAC filter.

ACTIVATED CHARCOAL FILTER
NOTE:Numbers in parenthesis refer to numbers in illustrations.

Removal & Installation
The activated charcoal filters are located in the A/C housing behind the glove box.
Move passenger seat all the way to the rear position. Remove 2 bolts retaining cover under lower right side of instrument panel. Retaining bolts are near lower edge of instrument panel. Fold cover down and disconnect electrical connector. Remove cover.
Remove activated charcoal covers (1) by pressing in retaining clamps (2) in direction of arrow. See Fig. 1.

CABIN AIR FILTER
NOTE:Numbers in parenthesis refer to numbers in illustrations.

Removal & Installation
The dust filter is located on the passenger side of the engine compartment, in the fresh air intake.
Open hood. Unscrew plastic nut (1). See Fig. 2.
Release left and right snap lock (2) on dust filter housing (3). See Fig. 2. Swivel dust filter housing (3) in direction of arrow and take off.
Fig. 2: Removing Dust Filter
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
NOTE:Dust filter should never be cleaned; replace filter if dirty.

Remove dust filter (4) from dust filter housing. See Fig. 2. To install dust filter, reverse removal procedure