W126

1983 300SD Turbo: Light black smoke at idle

The symptom is unburned fuel at idle. A light puff-puff of black smoke -- not heavy, but visible, at 700-750 rpm with car in gear and A/C on. Much less smoke when the tranny is in neutral, A/C off, and engine is idling at 800 rpm. The presence (or absence) of an air filter has no effect. Except for this bit of smoke, which is embarrassing at stoplights, the car runs and shifts great. 0-60 in 14.5s, and I measured 10 psi boost during hard acceleration. On long trips getting 20-22 mpg (milage verified with GPS).

Chassis Model Number

W126

Forums

Diesel Engine Specific Aid

1983 300SD vacuum locks but not unlock

I have gone through the vacuum lock lines and tested each door to make sure I dont have a leake. The doors will all lock when the drivers door is pushed down from inside or with the key. But will not unlock the other 3 doors when the drivers door is opened. The trunk lock holds vacuum but does not unlock other than with the key. When I push the drivers door down the motor in the trunk comes on and goes off. When the drivers door is opened (lock pulled up) is the motor in the trunk to come on and push air to the other 3 doors to unlock them?
Thanks for your help Jim Hunt.

Chassis Model Number

W126

Forums

Body and Interior Specific Aid

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