You should identify what the spot is caused by. Is it oil? Is it coolant? Is the engine losing oil? Is the engine losing coolant? Is the engine losing PS fluid?
Where exactly is the spot you're seeing? Is it on the passenger (right) side or the driver's (left) side? FYI: right and left are determined by sitting in the car facing forward.
If it's on the right side, it might be the hydraulic fluid from the front engine mount leaking out. That could create a small spot for a while, then it will go away. AC condensate can stain- if there is a lot of crud inside the AC plenum- but I doubt that's what it is since you said it was an oily spot. AC condensate should dry up, but if it was dirty, then you might see some brown stain, but it would be dry brown stain. You could probably clean that stain up easily with a household cleaner. For oily stains, use "orange" hand cleaner from an auto parts store. A little dab, rub with a rag, rinse, rub, and now that spot will be cleaner than the surrounding concrete. Don't dally if you want to clean it up. The longer an oily stain sits on concrete- the less likely that it will clean up.
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Originally Posted by the user formerly known as ZX3_Chick
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