My 1985 Mercedes 300D Turbo has been loosing power. I'm hoping it has to do with vacuum and not the fuel. It started with my car loosing power while driving. It was acting like fuel starvation. Also the car would rev to really high rpm's before shifting. So after much searching and buying parts such as lift pump, fuel lines, cleaning the tank screen etc... I found a crack in the Vacuum line running off of my ALDA. So I replaced the vacuum line and it worked fine for about 4 days. Now the same thing is happening, only I notice that I'm only loosing power when I get to higher RPMs. I'll drive, it will get to about 3-4000 RPM's and loose all power. Then I can't move it, but after a few minutes I'm able to drive it again for another 50-100 yards or so and the same thing. I opened my hood and noticed a very little bit of smoke coming from the intake manifold. I then remembered that I had also cleaned the Banjo bolt that connects the vacuum line to the intake manifold. While cleaning I lost one of the washers down in the car somewhere. So I replaced it with a washer that was not exactly the same size but that, I feel, should work.
Could it be I have a vacuum leak here? Or is this something else.
And does anyone know where I can get a new banjo bolt for the intake manifold, or at least a new washer that matches exactly. I couldn't find any a the local hardware or auto parts stores.
Any help, PLEASE

 

Sorry, I should have included that.
Yes, I've replaced the fuel filter (both) as well as run a diesel purge.
The car idles fine, but once I build up the rpm's or try and move the car it just looses all power.

 

My 83 300D exhibits similar problem. It drives fine but loses power then stalls randomly, especially uphill. It will restart again if I wait a while. I suspect is the fuel strainer clogged in the fuel tank. I will try to get to it next weekend. In the mean time you can check it out.

 

Yeah boblo, I checked the fuel tank screen already. It was fine. Thanks though.
Good luck!
I'm really thinking it's a vacuum issue right now.