I have a 85 300D with 179,000 miles on it. It has a turbo. It is just not making power. As long as you keep the RPMs up it goes. The turbo engages and it hasdecent power and pours black smoke. When you go up a hill you are lucky if you can get to 20 mph, and it smokes up the hill. It starts easy, and idles fine, run it up in park it's fine. Put a load on it and no power. Any Suggestions I am at my wits end.

 

Change the Air filter and fuel filters.

 

They are brand new, thanks

 

I called a mechanic friend of mine and he thinks it has something to do with the turbo. I will take the car to him and let you all know whats the out come

 

If your Fuel Tank is contaminated with something growing in it a new Fuel Filters can getting restricted within an hour.

If you do the Filter changes yourself it is cheaper to change the Filters and see what happens (if you think the old Filters might be good put them some place clean and re-use them later).

When my Car was dealdy slow and only acted normal when I put my foot way in it was when the Linkeage between the Fire wall and the Fuel Injection Pump Throttle Arm was extremely sloppy.

When I took out the slack the Car ran normally.

 

Very good point. Is there a good additive that can fix a containment problem, or how do I fix this problem?

 

Startron Boicide is often recommended because it has an enzyme that breaks up the dead grown into small particles and will not plug up your Filters as often as just a biocide.

 

What you need is a good, honest mechanic.

I had problems with my non-turbo, no power at all, smoking, and found a new, great mechanic, who fixed this problem. In my case it was the fuel pump timing and the valve adjustment.

It can be a lot of things. Stop driving yourself nuts, and drive your car to a good mechanic. If you don't know a really good one, put your time into researching one in your area.

 

The problem is that with out someone recommending a specific Mechanic is that trial and error to find one who can do the job; and even harder to find one who can do the job that is honest.
Your only real protection is to learn enough about your Car to weed out the good from the bad. You have to invest in yourself.
I think it would not hurt for the Owner to clean out the Boost Pressure hose/Tubing that comes off of the rear of his Intake Manifold all the way from there to the ALDA on his Fuel Injectin Pump.

 

try switching your feed and return lines. its not long term but it will tell you if its a fuel screen issue.

 

(old thread, already posted in it)

 

you could also try changing your transmission fluids,and also its filter, i recently changed my tranny oil and found out that the tranny filter was so dirty and the oil was very dark, after the all the old atf were drained of my 300d was running smoother and faster, climbing a hill was easy

 

Ok, I broke down and took my 85 300D to the mechanic. He states he is getting plenty of vacuum to the trans, but the problem is the vacuum does not drop at all. So he is looking in to it. Anyone have any ideas? Thanks

 

The Vacuum going into the Vacuum Valve that supplies Vacuum to the Trahsmission sould only be 10-15 before it goes into the Vacuum Valve. There is a restricted Fitting in one of the Plastic Nipples that comes off of the Main Vacuum Line.
This place has a good but long article on Transmission adjustments.
http://www.continentalimports.com/ser_ic20242.html

If you have a high Vacuum going to your transmission you should be getting really harsh shifting.

But, I cannot relate too much Vacuum getting to the Transmission with the problems you were having at the begin of your thread.

 

Update, the transmission problem was a vacuum leak, the performance issue was the injector pump, I am in luck my buddy had a brand new one and gave it to me because he does not have a Mercedes anymore. The shop is putting it on and I should be in business, just in time for $4.00 diesel.

Thanks to everyone for their help.