If your car is like my 855, you may be able to take the panel for access to the right brake light and look for a wire loop. Check your owner's manual. You may be able to free up the solenoid with that loop.

You might also look for the lock pin behind the fuel door - on our 850s there was a rubber grommet around the pin (if it has one!) that folded over and hung the lock up.

Take look at the plastic trim panels around the tail gate and see how they overlap.

On our 850s, one had to start with the top middle of the interior trim and work your way around to the right interior panel.

If the door swings freely, could be the spring that holds it shut is broken or missing, or the hooks on the hinge for the spring are broken. The spring kind of resembles 2 safety pins end to end with the heads cut off. Also, the fuel door solenoid locks after a ten minute delay after locking the doors with the key or remote. If the spring is missing, the hinge is probably broken.

For the record the user bulletproof did not post the original message. I was posting with no login information and somehow my post was linked with the wrong user. Sorry.

Sounds like previous owner broke it in the open position :)
You will have to remove the right rear panel to get to it. Then you can determine the proper fix.

Brakes are a piece of cake. The 2 slide pins have a plastic cover and either take a 7mm hex or a 40torx. Please clean and regrease the slide pins, I found a tube of synthetic brake grease for $1 at the checkout counter of my auto supply store.

The caliper will push in with gentle use of channel lock pliers.

Klaus
--
I still miss my 164