I remember when fitting my CB aerial in the back, when i took the cable through the rubber boot/sleeve in the back door some of the cables were very tight. You might want to take a look behind some of your trim and check for and trapped cables as something might be rubbing on metal.
Also if you've had anything heavy in your boot with your rear seats folded, under the right hand side rear seat and under the carpet is wiring to your fuel pump, and the wiring follows underneath a metal clip, make sure it's not trapped underneath here if it's anything to do with the fuel pump and the metal clip can easily get squashed.
