I have a 1989 190e 2.6 auto. Today I noticed a thin pipe (black with
2 red stripes) coming from above the transmission housing that ends in
a rubber connector that looks like it should be connected to something
but it isn't.
I'm guessing it's a vacuum pipe of some sort (for the vacuum
modulator?) as there is another of the same size (this time all black)
that comes from a similar direction and connects with a similar rubber
connector to the inlet manifold, number 6 port.
The car has recently had an oil change so I guess it must have been
dislodged when this was done. Both pipes pass very near the filer.
Anyone got any suggestions where it should be connected? I can't find
anything obvious. Even better, anyone with the same model who can
have a look at theirs and report back?
If the vacuum line to the trans is disconnected you should experience
extremely hard shifts.
It is common that the vaccum line gets pulled off during a ham fisted filter
change. Mine has a small rubber elbow that connects this line to the vaccum
port behind the oil filter.
Thanks for that.
The line that's disconnected doesn't appear to be that one: I have
tried disconnecting the other black pipe (which is currently
connected) to see what happens and I do indeed get very hard shifts,
so I put it back on!
I couldn't find anything behind the oil filter that it could connect
to. Do you mean it connects onto the manifold?
Anyway, I'll have another look in the daylight.
On Thu, 2 Dec 2004 01:57:14 -0800, "Peter W Peternouschek"
On my old '82 123, the black pipe is a vent line that goes through the
firewall into the cabin. That way, when the system releases vacuum, it
intakes clean air into the system. The cabin air is clean.
In the back yard, under the oak.
Thanks for the help, I have managed to find out where the pipe should
be connected :-)
The black one is connected to the Vacuum Modulator, a red disc shaped
object of left-hand side of the transmission. OK there.
The black pipe with red stripes should have been connected to another
pipe that runs across the firewall within the engine compartment and
then through it to join to the main vacuum system where a feed from
the manifold splits into loads of branches for the ventilation
control, etc. (near the master cylinder).
It seems to be connected with a solenoid so presumably a vacuum isn't
It travels down the right-hand side of the transmission and joins onto
a white cylindrical object on the transmission, the same thing that a
cable from the throttle assembly connects to.
Out of curiosity, does anybody have any idea what the white object
does and why it would need a vacuum? I guess it's how the
transmission knows the trottle position but why the vacuum? Having
the vacuum disconnected didn't seem to have any affect.
On Wed, 01 Dec 2004 22:22:45 +0000, Chris_Orange
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