My father just bought this car it is very slow. I just replaced all glow plugs he had two bad. For the running issue I replaced both fuel filters, air filter while I had intake off I cleaned the vac fittings on intake and Alda, I cleaned egr checked all vac lines, didn't find any broken. The Alda and egr were pretty oily having a lot of oily residue around them.the car is very nice with only 200k. The car has no power and the trans shifts very hard. I have a couple ?s when I hook the vac hose to the flapper valve across from the egr it closes the valve making the car bog down. That vac hose is pulling vacuum at all times. Also I have read a few threads about the EDS computer control this car has but I really dnt understand how to test the system and pull codes from it? I have read codes from w124 e320s is it he same? any help is appreciated!

Sounds like you have a vacuum problem. If the engine shuts off with the key, it's not that big of a vacuum problem. Transmission shifts have to be sorted. Make sure there's adequate vacuum to the vacuum control valve (VCV) that hangs off the driver side of the injection pump. Source vacuum goes into the taller aft fitting. The vacuum signal to the transmission modulator on the driver side of the transmission connects to the VCV forward fitting with the geen cylinder. The black line on the side of the VCV is of no consequence.

As for the wastegate, if sorting other vacuum leaks and issues doesn't bring back the power, consider if it's worth diagnosing rather than just putting matters back in nature's hands - http://www.peachparts.com/shopforum/diesel-discussion/212097-wastegate-actuator-swap-om602-962-a.html

Sixto
87 300D

My money is on the EDS computer garbage preventing the wastegate from working. Follow sixto's advice and the car will perform like a totally different car.

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Which computer is the EDS? Part num? I have buddy that has the same car I could try his if I know which computer it is. Again anybody know how to check my car for codes? As far as my hard trans shift. How much vac am I suppose to have at modulator?

The EDS itself rarely fails. It's the sensors and actuators it works with that can drive you nuts because of the rudimentary OBD. I haven't read any worthwhile discussion here about error codes or what the diagnostic steps are given certain codes for that engine. Those that want to preserve the system throw parts at it. Usually vacuum amplifiers. Maybe you can borrow vacuum amplifiers from your buddy. Get your hands on a factory service manual if you don't have one.

Sixto
87 300D

There is a direct line from the engine vacuum pump to the VCV so it should be close to the same value of about 22"Hg. IIRC the line to the transmission should see at least 15"Hg at idle tapering to 0 at WOT.

Sixto
87 300D

I would not mess with the VCV until (assuming lack of boost is your problem) until you get the wastegate actuator working properly.

Have you connected a boost gauge up to see if you are getting any boost?

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Ok so vacuum amplifiers are the most common issue. I will check them out tomorrow and see about the boost situation. The vacuum amps are the saucer looking deals not the little brass looking valves that have an electronic hook up and three vac ports right?

Correct...

I've tested several that checked out ok and still had no boost issues.. I would just get rid of all that stuff and do the pressure activated wastegate actuator mod. It is very easy to do and would save you tons of frustration. It could be done in the fraction of the time it would take to test all the vacuum and electrical stuff related to the EDS.

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And fraction of the cost.

Sixto
87 300D