[240_benz]

One of the PO's who abused my car years ago disabled the locking system. I'm already fed up with manually operating them, and I don't like worrying about someone stealing my precious Diesel fuel because the fuel door can't be locked.

Where should I start investigating first? When someone decides to disable the locking system is there usually a typical spot that takes care of the whole thing in one fell swoop, or are the vac lines cut at each lock? The reason I ask is so I can have a better idea of where to start the process of re-enabling my locks.

Some background info that might help.

1982 240D U.S.
California model
manual transmission
manual climate control
EGR still in working order
The vacuum reservoir is still in the trunk with the yellow vac line connected to it.

That's about it.

 

[digitalfx]

It could be blocked under the hood near the firewall or in the door itself.

 

[ducatipaso]

i would start looking for a bolt or a golf tee in obvious places.
are you sure the system is 'disabled' and not just 'bad'

go to your LFAPS and get a mityvac and get ready to hunt

is diesel fuel theft really a problem in upscale marin county?

 

[240_benz]

As far as I know the locks just don't work. None of the other systems that are operated by vacuum are affected. Just the locks.

Fuel theft made the headlines around the Bay Area for a little while when we saw $4.00 a gallon. As for Marin, it's not an issue.

I guess the bright side of all this is I now have something to do over Spring break. Woohoo!

 

[Rmac58]

It could be blocked under the hood near the firewall or in the door itself.

I would think the lock system, if unplugged under hood, had a leak. Start at the fuel door and work your way toward the front, checking for leaks in the diaphragms of each lock.
Good luck, I'm sure it's a tedious process.

 

[MBeige]

It could be anywhere. Check the hood for the yellow check valve. Is it connected? Get a Mity Vac and test that line. If it does not hold vacuum a line is not connected. Start working higher up the vacuum line branch and work your way to more specific ones.

On mine, I went ahead and replaced each actuator. Works flawlessly now, and I have an easy 5 cycle locking system once engine has shut off. The vacuum also holds for a week so far. It was not cheap but I'm keeping it for a long time so it's worth it.

 

[240_benz]

The check valve is still there. Once I get the mityvac I'll begin testing the whole system. I think this weekend I'll pull the door panels off and have a look at the locks.