'81 240D will not stop running

Hello, I have an '81 240D that has been acting up. The engine will not stop running after the key is removed from the ignition. I have to go under the hood 95% of the time to push the STOP button to kill the
engine. The other 5% I can kill it by shutting off the ignition and put it in gear. Another thing that began about the same time is the door lock will not lock the passenger doors when using the key in driver door.
This is my first M-B purchase a few months ago, and the electrical sys is unlike anything I'm used to. I'm sure this is a common problem - even though I did not see any related postings)
Regards, Terry
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
The engine's shut down, the climate control and the door locks are all vacuum operated. There's a vacuum leak somewhere, probably in the driver's door lock - one of the usual suspects - that's lowering the vacuum to the point where these applications don't work.
It's a project if you're handy, otherwise take it to an independent M-B shop.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks T.G., I tested this this out and shutting off the ignition with the driver door locked does shut off the motor. Does this mean the problem is inside the door behind the pannel? Regards, Terry
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
All the door locks have vacuum bellows and, the driver's door I believe, a vacuum switch. The leak could be in ANY door, the trunk or fuel door lock. The last two are easily checked - with your ear inside the trunk as the engine idles. The doors are an elimination game. You car is the "right age" for this affair.
Take a look at some on-line parts catalogs to see these parts. www.thebenzbin.com or www.buymbparts.com
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Did you recently have your oil changed? That's what happened to me. It wasn't a vacuum line but rather the 3 way vacuum connector located near the top of the oil filter. Before you go digging around the rest of the car check the vacuum lines and connectors in the engine dept.
Toblin
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.