Engine won't shut off when doors are locked???

[bnaquin]

Sounds bizarre but when my doors are locked, my engine won't shut off. If I unlock the doors via the drivers door, all the locks slowly come up and about 10 seconds later the engine slows and dies.

I'm assuming I have some kind of vacuum issue but if anyone knows which direction to point me I'd appreciate it.

FYI: All my door locks function slowly but the fuel filler door and trunk locks do not work. I've also recently replaced the yellow and white three way vacuum valve just in front of the drivers side firewall.

This applies to a '83 300D with 141k miles.

[anghrist]

This requires a systematic process of elimination.

Start with:

1) Check Valves
2) Master Locking Cylinder Element
3) Reservoir(s)
4) Each Door Element
5) Gas Door Element
6) Trunk Element
7) All lines and connections.

[bnaquin]

Do you know what the vacuum pump should be pulling if it's working properly?

It's not unusual, you have a vacuum leak someplace in the "locked" portion of your door lock circuit. This part of the system is made up of yellow lines with a red stripe, it runs from the driver's door, under the front floor mats to the other doors, the fuel door, then the trunk lock. The easiest way to diagnose it is to use a mityvac and check each of the tees under the mats until you determine which portion of the system has the leak.

Hint: I've had to replace my fuel door actuator twice.

[bnaquin]

Awesome. That's where I'll start. I've been meaning to fix the fuel door and trunk anyways. I'm assuming the best way to check for the leak it is to put the mityvac on the circuit and see where the vacuum bleeds off?