AXV

So basically this is what's happening.

Few weeks ago I noticed my car would start dropping RPM's and my electronics would start flickering (mainly headlight) when I take it out of gear; to the point where the car just turned off. If I give it gas and keep from the rpm higher it wont stall but after while that just didn't work. It got to the point where my car would lost all power mid turn while trying to downshift. Like I mean ALL power. I could not even turn on my hazard lights to signal my car was fucked.

I have a few aftermarket crap installed on my car so I thought maybe something was up with them. I took them all off. Took it out for a spin and it was all normal. Or so I thought. I got to work and parked my car and turned off my car. Boom lost all power. No electronics work; including dome light, cluster clock, hazards, etc.

However, once I close the door the cluster clock will go back on. If I open the door it goes away again. If I put in my key and turn it nothing happens and no power. I wait awhile, check fuses and it starts back up like nothing happened. Take it for a drive and all is good. WTF!?

Battery is good
alternator is good
starter is good
fuses by the battery all check out

Car is a '92 240sx KA24DE; engine and ecu all stock.

I am totally lost. I found a few posts on zilvia as well as other s-chassis forums that have the same shit going on but none of the posts have a solution.