I have a Ford Fiesta on a UK P reg (1997 model). I was recently running low on engine oil and so decided to fill it up. Nonetheless, like a plonker, I poured 5 litres into the engine (which now seems a bit excessive!) Since then, when I start my car after leaving it for 12 hours or so, lots of grey fumes pour out of my exhaust for about 10 seconds or so and then its fine. If i use my car and then leave it for an hour and then use it again, its fine with no fumes.
Any ideas?