Time was short so I figured this out myself: I went to my local dealer expecting to order and wait for a part. I figured if I looked at the part I could tell how it attached. To my surprise they had them in stock which I took as an indication it is a common failure. Cost: About $15.00. Before you do anything look and make notes as to how the metal spring is attached. The plastic hinge is attached to the body by way of integrated clips that expand with plastic pins. To get the hinge off you take a very small diameter punch and gently hammer the pin inward to the body. There are four pins. You must look carefully as they look like stampings from the mold. [The plastic pins are no more than 3/8 inch long which is apparent when you by the new one]. After punching them in, the hinge and fuel filler door pulls right off. Carefull not to drop the door and scratch the paint. I lubed the metal spring clip and pressed it into the new hinge. I used some WD40. You will see a loop that is attached to the door; take a needle nose and gently pull up to get it out of the hole. I advise starting the pins a wee bit first or they will pop off. The tether on my gas cap was broken. They said I would need to purchase a new cap: $30. I used a black nylon zip tie, punched out the old tether ΐ pins just like the hinge], drilled a 1/16 hole in the flat end of the tie. I secured the wide fastner end to the lower spring end of the spring clip as the fastner was too larger to go over the bracket on the door. It is a little stiff and I will see if it lasts until my son sells the *#$$ car. BTW: Costco offers 15% discount coupons for parts and labor for some dealers. I was fortunate that the closest Volvo dealer was named. The parts people didn't know anything about it until I showed them the coupon and another man likewise showed up and had printed his. Alas Volvo service doesn't compare to my experience with Lexus or BMW and a new S80 T6 cost very nearly the same as a 5 series BMW. Hope I didn't offend die-hard Volvo owners [I've owned Volvo's since my first 1971 164E] but our family won't buy any more Volvos.