Is there a catalytic converter in a 1995 E300D?
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From: Massachusetts
2018 GLE350, 2014 G550, 2000 SL500, 1980 TR8, 1995 E320 Cabriolet
Your car may be equipped with a thermal oxidizer. It's similar to a gasoline catalyst, but is designed to simply burn (oxidize) any extra unburned hydrocarbons in order to reduce emissions, reduce the "diesel smell", and reduce the particulate (soot) emissions. They are designed to operate in the oxygen rich environment of the diesel exhaust stream instead of the near stoichiometric conditions found in a gasoline exhaust stream. They provide no NOx reduction catalytic activity like a gasoline catalytic converter.
The MB EPC shows a version of the 300D exhaust with and without, so I'm not sure what you have. As for the "sound" without it, any device inserted into the exhaust stream will quiet the sound. Typically an OEM will design-in a less flow restrictive, but theoretically louder, muffler to compensate for the increased back pressure caused by things like thermal oxidizers, catalysts, etc. The overall sound level of the exhaust remains low because of the baffling (quieting) effect of the cat/oxidizer. If you remove the device (oxidizer), things will likely get louder (and smellier).
Sorry if I caused confusion . . . need to avoid the "Quick Reply" button.
The MB EPC shows a version of the 300D exhaust with and without, so I'm not sure what you have. As for the "sound" without it, any device inserted into the exhaust stream will quiet the sound. Typically an OEM will design-in a less flow restrictive, but theoretically louder, muffler to compensate for the increased back pressure caused by things like thermal oxidizers, catalysts, etc. The overall sound level of the exhaust remains low because of the baffling (quieting) effect of the cat/oxidizer. If you remove the device (oxidizer), things will likely get louder (and smellier).
Sorry if I caused confusion . . . need to avoid the "Quick Reply" button.
