You should have a GOOD body shop look at your car and give their opinion of your problem.

GOOD advice isn's cheap, but it often is worth the price, besides, most body men will look for nothing.

There is a remote possibility that you have an incomplete lacquer paint job. Lacquer is dull when it is freshly painted, and sanding and buffing are required to bring the finish to a great shine.

Your comment about solvent is interesting.

--Enamel "cures" and has a tough coat after curing, with a softer paint under it. You do not mess with the finished product as you remove the tough coat.
--Laquer merely dries as it is solvent and pigment applied in several coats. When you want a fresh shine, you just rub the surface smooth, revealing more of the same. Until you go through the paint.

The right solvent could wash lacquer off.
--
96 855R, 95 855,854, 90 744 Ti - 340,000 Volvo miles put on 7 bricks

I wouldn't jump into anything until you have researched it a bit more. Depending on what is causing the dullness you might be able to rescue the paint, or you might need a new paint job. Generally dullness is caused by the surface no longer being perfectly smooth. This can be due to oxidation, paint failure, exposure to a corrosive compound, or any number of other things. It can also be due to failure of the subsurface under the paint.

I suggest lurking a bit at autobodystore.com or posting a question there. Lot's of expertise and some good suggestions. The site is a good place to buy basics for body work and paint as well. No affiliation, just a satisfied customer.

Metallics are hard to bring back. I'd opt for a paint job. Remove everything you can from the car including door handles, all lights, all trim, bumpers, everything that doesn't get painted. If the shop removes the stuff that's labor. If they just mask over it I can guarantee you won't be happy with the results. After the car is painted you can really make it shine by color sanding and buffing. Use 4000 grit paper, lots of water and a good buff out for a quality finish. It's a dirty world, even in spray booths and lots of crap ends up in your paint. Sanding and buffing removes most of it. How long the job will last depends on your climate, covered parking and overall care of the paint.
--
Roy Olson

Them metallic paint colors just don't come back the way good old solid color original Volvo paints do... And paintwork just ain't cheap. Best bet for cheap would be to pull all trim pieces off yourself, do as much prepwork as you can do, and take it to your local budget paintshop for a respray. Spend extra for quality paint... THose places do a pretty good job of painting...its the prepwork and cheap paint where they cut corners to save money.

YOu *might* get lucky though in saving the paint you've got... find a discreet spot that is faded, and try sanding it... wetsand with perhaps 1500grit, then 2000grit. Then go gitcha some good polishing compound, and a good hand held buffer, and see if it comes around. Sure won't hurt anything... it is sorta like work though.

Best of luck with it!
-Matt