with mr.clean magic sponge...
Last resort, if the oil and tar won't come off with regular cleaning brush, you can use a pressure washer surface cleaner from bestcargurus along with your pressure washer, that will surely do the job.
blacktop tar cement pavement
To take tar off a jute rug, first take it outside to shake off loose particles. Dampen a clean cloth with club soda and rub affected area to gently wipe off tar.
use somegoof-off or paint thinner or gasoline
cracking
Kerosene works very well and will not harm the windshield. Brush it on and let sit for a minute, then wipe the tar off. Wash thoroughly with alcohol.
The only thing I have ever had luck getting old hard tar off of anything is gasoline. I wouldn't recommend using it in the house though unless you have alot of ventilation and you clean the gas off the walls with bleach or some other cleaning agent.
powerwashing
I Have always used WD-40 to get Tar off my cars. It just wipes off with the WD-40 then I clean the WD-40 off with dawn dish soap, and then apply more wax to the area. Hope this helps you out.
Any petroleum based product should work. WD-40 is one.
the best way to get paint off your driveway would be mineral turpentine.