Right, before I start off I want to say that I'm NOT trying to start another "which petrol is best" debate (don't know why, since the Auto vs Manual has made it's quarterly appearance, so we might as well get this one out of the way too before xmas lol).
For the last 8 months or so I've filled up with nothing but Shell Optimax, stuck to it religiously. When I first bought the car there was no smoke on startup - nothing at all.
Since then I've been getting a slight puff of blue smoke when starting up for the first time in the morning. Lately with the colder weather this has developed into a small cloud, which has got me considering replacing the stem seals.
However two days ago I filled up with BP ultimate because I had no other choice. I've nearly used this tank up now, and I've just been out and started the car..... no smoke at all I'm going to stick with ultimate for a few more fill-ups to see if this was just a one off.... but worth finding out if anyone else has experienced this!