Door locking intermittently (not working, rather)

[CorsePerVita]

So I realize this will require me pulling off the door panel but I figured i'd see if someone had an idea so I know what to look for once i am in there.

Now and then, the car refuses to lock from the outside. If I lock the car and shut the door, obviously I cannot open it if I go in till I unlock it.

Once in a while, when I lock it, I can grab the handle and it acts like nothing happened, and I can open it from the outside. I then have to unlock it, open the door, close the door and try it again. Sometimes it takes a few times and then if I try it again it's locked and can't be opened. I'm assuming something is sticking inside.

Any ideas what this would be? I know on my 944 it had a small rod that went from the locking mechanism to both the inside and outside and if it was loose it'd sometimes not work. Is the 911 similar?

Thankfully I'm still able to lock it, but sometimes I have to do it 3-5 times and it's embarrassing and horribly annoying. This developed a week or so after getting the car.

I figure since I'm installing a new stereo tonight and need to pull it apart anyway I may as well fix this while I'm in there.

[DRACO A5OG]

The white wire inside the door may be shorting out causing the default open position.

Once opened, peak inside and locate that white wire, I bet it is rubbing against something sharp ergo SHORT. just place some liquid tape and relocate with some puddy, you will be set.

Oh wait, you do not have the power locks, nevermind.

Then it is your latch inside may be dislodged, it may require handle removal to tweek it back to run the path of the locking mechanism

[rusnak]

There's a little cam fitting held on the end of the tumbler with an allen screw. The allen screw could be loose. While the key is turned to either lock or unlock, you can end up pulling the tumbler out of the door if the allen screw comes out completely. And you could end up losing the allen screw. It's pretty easy to remove the door handle once the door panel is off. A few allen keys, needle nose pliers, some screwdrivers are all that you'll need. I think a small 9mm socket is all you need to remove the door handle. This is a simple job.

[crashr]

I'm not sure if you have power or manual door locks. I had manual and had this exact same issue.

My door won't open from the outside - w/ pics

It turned out that when I took out the door mechanism (#22 in the PET diagram, page 252, of the 74-77 manual) that there was a metal roll pin that had fallen out. Somehow I found another one that fit perfectly and things were fixed. Without the pin the unit would begin twisting/rotating in a sense; as opposed to working in just the xy plane, and therefore only occasionally allow me to open the door when it was unlocked, or as in your case, lock the door properly. If you haven't taken your door apart before, when you do, take a look at the bottom gutter of the door for any small parts which have fallen out.

Hope this helps,

[CorsePerVita]

Apologies for not specifying, manual door locks. Thanks for the info guys I'll check it out.