Locks don't work after 30+ minutes
 

Hey guys,

My 83 300D turbo is running great but it has another vacuum problem. If I let the car sit for over 30 minutes the key only unlocks the door I stick it in. If I use the key to lock/unlock the car within 30 minutes of shutting the motor down all the automatic locks work (Will work at least 5 times).

I assume there is some sort of vacuum canister/accumulator that has a slow leak somewhere. Can someone help point me to the problem?

Thanks

id check the door vacuum actuators first. those are known to leak. then onto connections. got a mity vac and some golf tees?

Yup, you have a slow leak someplace in the system. FWIW, the last two times my system leaked it was the fuel door actuator.

There is a fuel door actuator? I've been just opening the fuel door with my fingers :confused: :o

The fuel door actuator would be the mechanism that uses vacuum to lock and unlock the fuel door.

uhh... at the risk of sounding like a total newbie (I am one)... where do I find the switch to open the fuel door? :o I looked around at the diesel station for it for a few seconds then just went around and opened the door with my hand. It had no resistance or anything.

on my system which works.. when you lock the doors it locks the fuel door and trunk..

when i unlock the fuel door and trunk unlock and i just push on the hinged end to pop open the fuel door.

Pushing on it with your hand is the only way to open the fuel door. What we're talking about is the mechanism that locks/unlocks it. When you lock your doors a small pin should go through a hole behind the fuel door, locking it shut. The pin recedes when the doors are unlocked.

Thanks for clairifying that.

How hard is it to check if there is a vacuum leak at this mechanism?

The fuel filler lock actuator is between the fender and the trunk liner just aft of the fuel filler cavity. Peel back the trunk liner to get to it. Maybe you can get your hand in through the trunk hinge area and feel your way.

I believe the vacuum reservoir in a W123 is that bunch of 'balls' hanging under the parcel tray behind the rear seat. There might be another vacuum reservoir in the left front fender behind the wheel.

Sixto

The check valve (near the fuse box) may also be a problem.


atleast it was for me.