Hi there, Im wondering if anyone would know what the thin hard plastic tube that comes up (or down) from the rear of the engine and curves through a clip and ends up somewhere in the general left-middle or rear of the engine area is for?

It looks like it broke off or disconnected from somewhere and I cant figure it out. Is this a vacuum line? Its probably only about 2 or 3 mm in diameter. ( I took some pictures but dont have the files with me)

My transmission has be running rough for the last few months, Heavy shifting and sometimes erratic and doesnt shift at the right time. Ive been reading some posts about the vacuum lines and trasmissions and have been told by annother experienced mechanic this is the first place I should look (the vacuum lines.)

Im still much a beginner machanic, but have a good mechanical inclination but havent worked on cars ever untill recently. I have the right schematics for the transmission vacuum lines however I cant easily read and understand the schematic as a guide where to look for these lines in reality and when it comes down to working on it Im a little confused as to which hose is which.

I would love a picture manual pointing out what parts are what. I have a Hanes but it doesnt go into the vacuum system. Do the MB CD manuals have pictures in them?

Lots of questions here. Thanks
Michael

What is the color of the tube?

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'85 300D Cal 280,000 miles
'14 GLK 350 60000 miles

Its Black- sorry probably important info to include.

I think that goes to the transmission modulator. With a helper, try and determine.
The smaller line on the right.
It needs to be connected.

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83 SD

84 CD

YES thats it, the one on the right. It looks like its either broken off at the tip or simply dissconnected. Im not sure where it should be connected to and how (clamp, glue, rubber seal? ) So would this be a plausible reason for the heavy shifting?

I just love pictures. They make things so much easier!

Edit: Well come to think of it... Looking at the picture, it might be the one on the left. The one on the right looks quite shorter from the one in my engine. (unfortunately the car is gone for the weekend so I cant see right now) I cant see in the picture if the one on the left is coming from behind the engine block or from somewhere else. If it is, and if its the longer of the two I think it may be the one on the left.

In any case It would be good for me to know what they both are for.

Could be the boost sensor line coming from the banjo bolt on the back of the intake and over to the overboost control solenoid. I believe that's the only line that routes around the back of the valve cover.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

85 is a lil bit different in the vac routing than the other 123 cars.

have you looked thru the vac diagrams thread stickied at the op of the page? there are some good pics there and diagrams, too.

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1984 123.193 372,xxx miles, room for Seven.

1999 Dodge Durango Cummins 4BTAA 47RE 5k lb 4x4 getting 25+mpgs, room for Seven.

Yes, the '85's are different in many ways. Jack the car up, on the drivers side of the transmission there is a modulator, mine's green, at least on '84's. The line from the VCV will end up there.

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83 SD

84 CD