Hi all, Did a 350 mile trip today from London > Hereford > London. My car started to tick over to 2,000 rpm at idle 5 miles from starting my trip. Normally it is at 1,000. I could rev it out sometimes where it would go back to 1,000 rpm. 150 miles later and I had an 'engine oil low' appear. This just after a major service at Audi London where they changed the whole 5 litres. I topped it up in Hereford with a litre as it was below the minimum mark (Castrol Edge 5w30). Got 50 miles approx and up it pops again - 'engine oil low'. I stop at Warwick Services and realise there is a slight oil leak from the sump area. I could also see oil within the engine bay itself. Temperature gauge never fluctuated from 90. Always spot on. RAC couldn't deliver, so I set out stopping often all the way home by topping it up with a further 2 litres. It's at minimum level again. Engine diagnostic light only appeared 10 miles from home. What is going on? I haven't hit anything that could damage the sump either. What are possible costs here? I have spent fortunes this year. This vehicle is fast becoming the costliest vehicle I have ever owned. £2k already this year alone. (2007 with 40k on the clock).