2.0 FSI engine noise

[synked]

Hi all,

I bought a A4 SE 2.0 FSI (04) a couple of weeks back. When I first got the car I noticed how quiet it was, especially when idling - you couldn't even tell the engine was running (no vibrations or noise inside the cabin).

Last week, I started hearing a ticking sound from the engine, it sounds rough - you can hear it inside the cabin now and also feel an odd rhythmic vibration which wasn't there before. In short, the car now sounds like a diesel.

So, I took it back to the dealer, they inspected it and said an oil change would sort it out. After the oil change, the noise was still there (shocking..I know).

So, I took the car down to my local Audi dealer. The Audi engineer took a look and said it did sound rough, but that was quite normal for an FSI. He told me an FSI engine has two modes and in the 'fuel efficient' mode it was quite loud (saying that it's now running in that mode) . Basically, I was told it was quite normal and that there was nothing to worry about.

But, there are two things that are bothering me despite what the Audi engineer said.

1. Why was the car whisper quiet for the first week I owned it?
2. Why has the fuel consumption gone up around 5 MPG?

I'm looking for some advice really, since I'm still in a position to return the car or claim repairs under warranty if there is something wrong with it.

Thanks in advance.

Synked