I can sometimes hear a little pop when I push the button, but it seems weak and it won't open. First, how can you open it manually, and second, any hints on fixing it?

 

Look for the release cable in the hatch area. You may have to remove the rear panel/speaker cover. Spray some lube on it.

 

have someone pull on it when you hit the button then clean out the spring and spray WD40 in there

 

You might be able to reach the solenoid by moving the rear vertical carpet without taking out the plastilc wheel well cover. When I've had this problem, I stick a putty knife between the door and fender, then pop the switch.

 

more than likely the contacts on the release button are dirty. try cleaning or replacing the switch.
the release is an electric solinoid so there is no cable and i couldnt see wd 40 doing any good at all.
i would check the button and if thats not the problem replace the solinod.
pm me if you need any of those things.
--adam

oh yea if you cant get it open it is ok to just pry it open. the metal tab is pretty flexable, just make sure not to damage your paint.

 

There is a manual method to open the fuel filler door. It is stated in the owners manual (yes I still have mine from 1984)..

Like trochoid said, you reach behind the vertical carpet to where the solenoid operated catch is. The catch has a little sprung lever on the end that you can flick with your finger (towards the back of the car) to release the catch and open the door.

Not sure how to fix. My fuel filler door plays up maybe 1 time in 20. When it does I just open it manually and contemplate how to fix it then forget about it until it happens again.

 

Mine sometimes wont open, I just push or tap the door and then try again and it usually pops open. I'd rather have a locking manual door.

 

Yeah, mine does this once in a great while too. I just push on the door for a second, then try again. I just need to remember to give it a little squirt of lube one of these days...