Hi guys, new here... had my A3 for about 2 years now and had the same problem for majority of it! Symptoms; Terrible start on a cold morning..winding over for about 10 seconds and then starts with a splutter,, and if its really cold the revs will be going up and down for the first few seconds.warm morning and its running in half a turn. Temperature gauge doesnt move at all, doesnt matter how far i travel.. poor MPG varies in performance from day to day Things ive done to try and fix it... New battery new glow plugs starter motor checked Egr valve cleaned Remapped new thermostat new temperature sensor... although this did fix it for around a week... new timing belt and water pump. Would be a massive help if any of you guys might have a clue, because its been many places and nobody seems to have a clue!!!