I have an A6 2.4 V6 avant quattro. Recently I have had problems starting when I leave it more than a few days. The engine turns and splutters for around 30 seconds before catching and running very rough, 4 cylinders with lots of smoke from the exhausts. I have had the Engine light on briefly a couple of times and I am low on power. The car has done 30000 miles. Any ideas?

 

Just to update you all on the problem:

The Audi Tech came out with his computer and found that I had a faulty water temp sender whcih was causing the fuel system to overfuel and cause flooding at startup and an over-rich mixture during running.

All done in 1hr and under warranty of course. He said that these senders are quite a common fault, more on the 1.8 engines than the 2.4, all in all a fantastic service.