95 E300D Soot in Rear. Catalytic converter? Oxidation Catalyst?
 

For the past six months or so, my car has been the recipient of soot build up. If I clean it, it will come back in a matter of days. It's only on the rear face of my car, nowhere else. I've also had this nagging, drawn out fuel economy problem that may or may not be linked. My friend told me that he could see (looking at the cat, not the trunk) that I needed a new catalytic converter. From reading other threads, apparently catalytic converters can get clogged and cause performance problems, hence my linking of the two problems. I've also read, however, that the diesels don't have a cat, but rather, an oxidation catalyst. Do they look the same? I only ask because my friend is pretty well versed in auto mechanics, and identified whatever it is behind the tailpipe as a catalytic converter. Some users said that some Mercedes diesels have oxidation catalysts, yet Wikipedia redirects "diesel oxidation catalyst" to "diesel particulate filter," which, if the article I read is correct, was not installed in diesel MB's until '03. Soooo, does anyone know if my car has/should have a cat? Could that be the source of my plight? Thanks in advance!

Your car has an 1 way ox cat. Just like every other 2006 and earlier catalyst equipped diesel. If you choose to replace it getting a generic cat meant for diesels will work.

-Jason

On my turbo, its within the first 30" after exiting the exhaust manifold; coffee can sized. Pretty easy to tell if it is rattling with the hood up and your thumb on the throttle potensioner.

I'm in the same boat.... I thinking of running a straight pipe or resonator of sorts to fill the void.....