Given the nature of asphalt and its chemical similarity to diesel oil (they're both petroleum-based, they both contain lots of impurities, black and gewey), once the stain is in place, there is no product that is going to majically remove the undesired diesel oil and leave the desired asphalt in place, and restore original color of driveway!

The only real way to get rid of stains is to soak/scrub the oil with good soap or detergent 3 or 4 times to get rid of the bulk of loose oil. Then coat the entire driveway with that black seal-coat stuff for asphalt (home depot, etc.)

Seal coat is just an impure petroleum product (black gewey liquid asphalt crap) similar in many ways to diesel engine oil, except for having lots more tar and solids with more volatile liquids.

I would think you want to get as much diesel oil up and let the rest "weather" and soak into the asphalt for a month or so prior to seal coating.

__________________
1984 300TD Wagon, 407,800 mi (current daily driver)
1985 300DT Sedan, 330,000 mi (gone to that great autobahn in the sky)