There is a plastic panel underneath the rear of car by back axel, held on by 3x 10 mm nuts remove these you will need a socket and long extension ,then remove pannel this will reveal fuel filter, then you need a philps or cross head screw driver to replac filter remove holding bolt and both pipes then replace.
Yes, inside the transmission.
Check out the related link for a DIY article including pictures on how to replace the cabin air filter on your Mercedes Benz.
Where is the brake switch in Mercedes Benz E320, 1999 located? How do I replace it?
How to locate and clean or replace mass air flow in Mercedes ml320
The fuel filter is under the car you have to remover the plastic cover under the car to get to the fuel filter.
What kind of wrench is needed to loosen the oil filter in a Mercedes Benz ml?"
where is the Fuel Filter is located: for a 1996 Mercedes Benz C280
oil filter on a Mercedes 190E 1986 is in the back of engine
Cabin air filters are used to help filter an pollen in the air. To replace a cabin air filter on a 1993 Mercedes 300 SE the glove box will need to be removed. After the glove box is off the cabin filter will be visible and can be replaced.
There is no PCV filter on that car.
There is a fuse for the "air" filter?!
replace transmission speed sensor for a E350 mercedes benz