Clear Oily substance (antifreeze?) leaking beneath passenger side

Folks and Gurus:

A couple of times this week, there has been a puddle (pretty large....8-10 inch diameter) of some sort of clear oily substance under the engine on the passenger side.

About 3 weeks ago, my coolant light came on. I added enough antifreeze to bring it back up to the proper level. Today I noticed I was a little low again. Rubbing a little antifreeze between my fingers was the same greasy texture and color as what has leaked.

This has only happened twice in the last week or so, so it doesn't seem to be a constant drip (no puddle in my garage this morning). Both times it has happened, I have been parked in my driveway as opposed to my garage. This makes me wonder if our drastic temperature changes this month are causing some sort of issue. Does that even make sense? I have no idea.


Thoughts? Help would be appreciated.
My car: 2000 323i, 97k miles

Have you looked around the engine bay to spot a leak? Perhaps check around the expansion reservoir when you topped it off. A good way to check the rough area of the leak is to put a cardboard sheet under the car, and chalk where your wheels are. This saves your garage/driveway from the fluids too.

And shouldn't you be adding a mix of antifreeze and water -- or at least testing the results to make sure you have adequate protection?

Originally Posted by KillnTime

And shouldn't you be adding a mix of antifreeze and water -- or at least testing the results to make sure you have adequate protection?

Yes. I am just being lazy and buying the premixed 50/50. I know it seems like it doesn't make sense to pay almost as much for the 1/2 and 1/2, but it saves me the chore of having to mix it, so I'll pay a few dollars for that.

Good point. Can we assume you mixed 50/50 with distilled water?

EDIT: Guess we posted at the exact same time.

Update:
I just went out there and checked it, and I did get some leakage overnight. I see that it is coming from the little access hole perpendicular to the passenger side tire.
On that note, I went ahead and setup a service at my dealer. I don't want to screw around with the possibility of overheating my engine.

Ideas on what this will cost me? Luckily BMW CCA members get 15% discount at this particular dealership (which is why I go there).