What would you use to clean paneled walls?

http://homeguides.sfgate.com/clean-wooden-paneling-vinegar-mineral-oil-89999.html

In the old days, TriSodiumPhosphate, A detergent. A paint supply store has the modern substitute. Use the foam it generates with a sponge.

Try Murphy's Oil Soap. It comes in a spray or concentrated. You may want to use the concentrated to make the mix a little stronger if the wall are that bad. To get rid of any cigarette smell after cleaning the walls, use Hot Shot Fogger Odor Neutralizer. It gets into the areas cleaning can't.

I found that an ammonia solution was the answer to tar/nicotine buildup. You'll want to use gloves to protect your hands and to rinse well with clean water. Use a good furniture oil to treat the wood afterward.

I would start with a solution of tsp and water, wiping the walls and rinsing well...it may take two or three washings to completely get rid of the cigarette residue.

Mix 5 Tsp of Borax with 1/2 liter of water. Use rubber gloves and goggles to wash down walls. Letting the solution sit for a moment takes care of any gunk. rinse with plenty of water.

I mean "wear" rubber gloves and goggles when you wash down the walls.

I agree with Molly - I have had to do this on some paneled walls as well. Yu may have to do it a few times . Change water frequently. I would first however do it in a small inconspicuous place to make sure it does not ruin the finish. You may also have to rinse them prior to applying the polish. I used a product by Scotts Liquid Gold to polish. Not sure if that is still available. Although TSP is a great product, I would be leery that it might remove any gloss finish that was originally on the paneling.