My car (a3 1.8tfsi 2008) takes a short while to turnover (but not every time). It is an intermittent problem and tends to struggle most when its warm. The engine light was on, then went off (even though the problem was still there) and now is back on. I have had the Cam sensor changed as this is what fault was flagged up as, but its still as bad. The car on the whole runs well, perhaps a slight hesitation when accelerating but very minor. It was last serviced in November. Anyone any suggestions what this could be? Cheers

 

Have you checked fuel pressure?

What services were performed when it was serviced last?