I'm know very little about cars. My car recently went in for its MOT, passed after a few repairs and had only been driving once or twice since. Drove it to work today and after a few minutes on the motorway I noticed a big amount of white smoke appear in my rear view mirror. It completely blocked out my view for a second, then after that I was getting a little but constant smoke when driving. I stopped, to see if there was anything blatantly evident. There wasn't, so I got back on the road only for there to be no smoke whatsoever for the rest of the journey.
One off strange incident I thought. Then on the way home for a very short spell almost the same happened, but without the initial BIG amount of smoke. Just a noticeable amount constantly coming out for maybe 30s. Then after that nothing.
I'm assuming it isn't good, but would like to have an idea of what it is before I'm completely taken advantage of by a garage due to my lack of knowledge of cars!!
The smoke looked white in colour.
I recently topped the oil in the car up so it should be at its max level, although if I misjudged the amount, I guess it's possible I may have put too much in.