You guys will need to be patient with me - I learned to drive in a Ford Anglia.

Does Stop / Start imply that if the car is stopped at traffic lights etc. then the engine stops - and when you press the throttle it restarts ?

Stop/start woks pretty much as RT's quote but its not only A/C demand can make it restart, if the systems sensors detect the battery is getting low for any reason it wil restart the engine, quite a surprise the first time it happens. On my BMW the system would not work when the air temp was below 4 degrees, 3 winters ago when it was really cold it never worked during December, January and February.

To the OP, my first 2 cars were Anglias, have had stop/start on my last 2 cars now. IMHO its a total waste of time, only saves a thimble full of fuel once a blue moon. The one good thing it does is bring down the RFL group, saves good money there.

Thanks BRs. I'll investigate further and see if the car has got Stop / Start. I would have thought that the dealer would know enough about cars and customers to have been able to explain that, Sadly, that is often not the case. Things used to be so simple, why mess it up by installing a feature that is obviously of marginal use !

Because Stop/Start gives much better figures in the official EU fuel/emissions tests - the fact that these tests are fast becoming totally unrelated to real world driving is immaterial to Europrats.