has anyone experience of stop start just suddenly not happening any more ? Car (S4) is 3 weeks old. Initially stop-start worked fine . Then this week, even with long journeys, just won't happen (the symbol with line through it permanently on in the cockpit). All the conditions in the manual (page 98) about temperature, battery, etc are all fine . He disengage button is clearly off... For excample, on motorway for 40 mins, clear run, Turn off into town, hit traffic . Expect stop start to work - just doesn't engage. Any ideas ?