ummmm, good chance of killing O2 sensors and converter. But it shouldnt mess anything else up, maybe foul the plugs. With that little diesel in there, i'd let it get to like 1/2 talk and fill it back up. The worst thing you could have done is put 93 in there. Octane rating has NOTHING i repeat NOTHING to do with "diluting" diesel. If anything, you just made it worse.

See, you have to understand how fuel works, which Nate, apparently you don't, so here's your crash course.:

Octane rating refers to how quickly the fuel ignites- the lower the rating, the faster it ignites. A higher octane means it takes more direct heat (ie- spark) to ignite the fuel. That's why you use 93 in high compression and boosted cars, because the heat of the intake and compression CAN pre-ignite the fuel (ping,knock etc...) Now, since diesel engines don't have spark plugs, the diesel doesn't use a ignition source. The diesel basically works off detonation. They have very high compression ratios that compress so much, the diesel self ignites and makes combustion. Now mixing a substance that takes a LOT of heat to ignite and mixing it with a gasoline that has a higher threshold before ignition is going to be your problem. If you would have filled up with 87, you'd pretty much not have anything to worry about. But with that 93 you are going to feel the car running like ass.