mx5cartalk.com

There was nothing actually wrong, but this groaning noise had started when the drivers door unlocked when you turned the car off.
Not when the door locked. And not always when it unlocked. But most times.
I figured it was caused by me not driving the car very often. And it probably was at least in part.

I had the trim off for a separate problem on the same door covered in a separate post.
So I PTFE spray dry lubed every moving part I could find related to the actuator.
And this appears to have immediately fixed the problem.

I suspect the cause was the leaking window allowing enough moisture into the door internals to faintly corrode at least one of the moving parts, and this was starting to make a noise, and maybe would have ultimately failed.

Well I spoke too soon
It was a problem that came and went. But now it seems to be back permanently. The lubricating doesn't seem to have worked.
So I am assuming the problem is getting worse and I have to replace something?

When I manually turn the key in the door lock...no noise.
It is only when the central locking automatically releases the lock when the ignition key is turned off.
While making the noise the action seems slower?

I think this thread is my problem.
Which means a nylon bush is failing.
Which is part of the solenoid.
Which is part of the door lock assembly.
https://forum.miata.net/vb/showthread.php?p=5007217#post5007217

Just got a price from Mazda on the door lock assembly...$451
And it's an order from Japan.
I've got no time to hunt the wrecker atm.
So I've just emptied another can of contact cleaner into the general area...sound has stopped again.
And I'll put the door trim back on and leave it for another day.

I could be wrong, but I don't think that Australian NB8As came with central locking, therefore yours would have to be aftermarket.

The simplest way to resolve this would be to remove the actuator and just use the key to open the door.

Otherwise visit an auto-electrician before you hand over any of your hard earned money to a dealer and get it diagnosed.

Also, as you are in Melb you can always drop into my place in Chelsea and I can assist with investigating/resolving.

J

Thankyou very much for your time and your generous offer.
I believe I have the dealer fitted central locking/alarm which they were doing at the time and apparently they were not very good. The original owners I bought it from mentioned that. And my mechanic recently said the same thing.
I have found if I leave the door open when I turn on the ignition, then close it, the doors don't auto lock, and then don't have to unlock, most of the time (which seems to be the thing with this setup...it seems to throw out random events from time to time).
So that should give me some extra time before it fails.
Yes disconnecting would be best. I am not quite sure yet how to do that and always live in fear of causing bigger problems when I fiddle
I think I will also keep my eyes out for a second hand drivers door lock assembly which is hopefully in better shape than mine.
I also thought I read somewhere that at sometime someone made up some of those nylon bushes which seem to be the culprit.