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1985 300 D Gold
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Discussion Starter · #1 ·
So I have to look the driver door to shut off the car...anyone know how to do this? It is messing with my gas millage...Im leaving for a trip on the 6th and want this fixed!!!! please some one help...it started right after a oil change!

85' 300d
 

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First: check the vacuum lines in the engine compartment. If it started right after changing oil, you might have loosend a line unintended. If you have an Euro-model don't forget to check adjustable headlights.

How about central locking system? Does it still work, when the engine has been out for a while? Check both opening and closing after a while.
 

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1984 300D Turbo
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1,606 Posts
as martin said it probably has something to do with the master vacuum valve inside the drivers side door.
you can always disconnect that in the engine compartment
and hook the shutoff directly to the booster line.. if you want..but then the other vacuum functions like locks would cease to operate.

i fail to see how this would effect fuel mileage though unless you had to leave the engine on all the time lol...[:D]
 

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various W123 chassis
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Martin T - 4/3/2006 3:19 PM

First: check the vacuum lines in the engine compartment. If it started right after changing oil, you might have loosend a line unintended.

This is the ticket. Anything else is uncanny coincidence. Locking the master valve is allowing enough cumulative pressure in the entire vacuum system to make up for what you unplugged in the motor bay when you did the oil change, allowing the car to shut-off. This happend to me just yesterday, and common because of the line arrangements.
 

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1985 300 D Gold
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Discussion Starter · #5 ·
The door locks do not work either... my car has been garage kept its whole life and has 165k on car. super clean and never abused...the tranny is hesitating to shift then does abruptly. it gets about 400 miles on the HWY but 300 in city. is this about right? I thought when I first got the car a little over a year ago it was lasting longer?!

is it possible that the vacuum pump needs to be rebuilt?

Im leaving for colorado ina couple days and would like this to be fixed before i leave
 

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W-1-2-3 Go!
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300mi is quite low for city driving, I average 25mpg usually at around 15 gal so that's ~375mi/tank.

Sounds like a vacuum issue when the transmission shifts abruptly after hesitating. There's a bowden cable atop the valve cover, you can adjust it to the transmission shifts smoother (and a bit earlier).

It's possible for the vacuum lines to be unconnected around the oil filter. Here's a diagram for your car:

1985 Cali version


1985 Federal version


Hope that helps
 

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1982 300sd turbo
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267 Posts
kerkhoforama - 4/3/2006 3:53 PM

help...it started right after a oil change!

85' 300d
who did the oil change? that was when vac line got pulled apart, follow the lines around the oil canaster and you will find where it is pulled apart is my guess[:D] also you do know how to manualy shut down ??
n0rt
 
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