Amouneeb93

Hello, first day for me in here and I’m so glad I got to join benzworld , I just bought my first w124 1990 300E and I got a deal on her but I was wondering what’s the common problems with these cars and what to check mainly .. also I’ve been having a problem with idling and driving like when I floor it it doesn’t wanna go like my 04 cobalt does at least lol I know no comparison but I’m new to this and I would love some tips .. thank you so much everybody !

ohollenbeck

Welcome and good luck with your new project. But your 1st mistake is asking after the fact, on anything about these nice old cars.
Seriously getting a deal can be just an allusion at first glance, and you may really have a money pit upon close inspection, I hope not.
Here is a common cliquish among Mercedes owners, "There is nothing more expensive that a cheap Mercedes"
I'm not a diesel guy, so others will have to jump in here, but they are generally slow, unless you have a year with a turbo, (not a 90 I think).
Even with a turbo, they are still relatively slow.
The condition of any of these used 124's is directly dependent upon the previous owners maintaining them properly, which usually isn't the case on a cheap one.
A common mantra with these old cars is there is usually $5K worth of deferred maintenance needing to be done, maybe more the cheaper you pay for it.

There is a standard list of common parts that fail over time/miles, post some pictures and some more information, Miles?)
Here is one common thing to look for, how long does it take reverse to engage, an early indicator of time to rebuild.
Vacuum leaks anywhere? there are a lot of vacuum lines in that car, leaks can cause problems.
Vacuum pods in the HVAC unit that control air flow, the membranes in them break and they stop operating properly, and they are(mostly) not available anymore. If you can't get the AC to come out the center vents, that pod is most likely defective, with no new part available, There are 6 or 7 pods, forget exactly, maybe 1 or 2 are still available, maybe.
Replace the ignition tumbler soon, don't wait until it fails, then real big bucks to fix, plus a tow.

So much more, your first post should have read, "I'm looking at a diesel 1990 W124, what should I look for before I make an offer?"
and the first responsible response would normally be, "get it inspected by a mechanic that knows w124's before you do anything".

Anyway, hopefully you won't have to spend too much money to get it running properly, good luck.