How often do you replace EGR back pressure filter?
 

How often do you replace EGR back pressure filter?

My car is 1992 300D 2.5 turbo. It has a filter near battery. I found the following numbers on it.

“three star” 000 078 08 56

4500158901

I think it is EGR back pressure filter, because it looks like the EGR back pressure filter picture at Fastlane.

If it looks old, or dirty, replace it.

Use ur judgement.

what is it? Does my 90 sdl have one?

Your SDL has one, looks like this:
http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1MB12FET61OI0V7E0Z&year=1987&make=MB&model=300-SDL-001&category=All&part=EGR+Back+Pressure+Filter

Mine is probably original and looks brand new? Whats the point of this thing? To catch oil if the vac pump fails?

I had to remove the battery to replace it.

I thought that MB part is opaque, but I found it has transparent cover: it became dirty.

By the way the MB part number of EGR back pressure filter is

000 078 06 56
not
000 078 08 56.

I put a Mann filter (aftermarket). Are aftermarket filters of lower quality than OEM?

Why not just add a block off plate and "fix" it once and for all.