1985 California-spec turbodiesels received a 'trap oxidizer' (soot trap) mounted between the exhaust manifold and turbo, which forced the air cleaner to be relocated and introduced unique, hard-to-source engine parts. Multiple owners report replacing the turbocharger twice and struggling to find parts; a 49-state car of the same year is considered clearly preferable.
The 1985 California trap oxidizer and one-year turbo parts
Mercedes-Benz W123 · mechanical