I've owned a few 123 diesels, and maintain an OM617 in my sister's W126 300SD, but I know almost nothing about the later diesels. We have a '95 C280 and I've become somewhat interested in adding a late model diesel to the fleet. As tempting as a new E320 CDI is, that's a lot of cash to drop on a car. I was shown a 1995 E300 diesel recently that looked interesting, as well as a 99 E300.

First off, what's the technology behind the mid-90s diesels? I know that they aren't CDI engines, but what is electronic on them? Timing? Fuel Pump? Throttle? Emissions? Were there many year to year changes that make one desireable over another? Was the engine in the '87 W126 used much longer than 87?

Second, what types of problems do the later diesels face? I'm used to doing things like dealing with vacuum leaks/issues on the 617 and chasing air cleaners all over the engine. Are the "problems" with the later engines similar in frequency and severity? I like shutting the hood on my sister's 300SD and telling her to come back next year.

Thanks for any info you can share with me.

-Tad