Hi everyone...
I know this may sound rather unclear and stupid, but sometimes I feel uncomfortable in my car because it doesn't act as usual.
Normally I fill it with the same gasoline... outside temperature has also been the same for the past month.
I mean, I can't find any clues about what might affect its behavior.

But in rides like these, it brakes with the engine somewhat stronger than ever, and the gas pedal is less responsive. I can hear the exhaust, but exhaust sound to acceleration ratio is not the same. Experienced this both in manual and automatic modes. Not that it loses all the power, it just doesn't feel fast and light as usual.
And sometimes the car is really fast and responsive, acceleration curve is wonderful.

No check engine signs, mileage is 30k kilometers, fully serviced - filters, oil, brakes. Am I being paranoid and my mood is the reason? Or maybe gasoline quality can affect car so strong? Or maybe it's the compressor? Anyway I would see check engine sign I suppose.

Also I had something like this with my Tiburon, but found nothing. No issues with Audi though.

Anybody has this? Please share your thoughts.

 

I had similar symptoms to yours (I could use full throttle and the car just wouldn't go faster) and eventually got a CEL with code P0251-13, indicating an issue with the fuel supply. Problem was found to be that the electrical connector on the fuel pump hadn't been clipped fully into place (at the factory?) and had worked loose - it was sort-of flopping about making contact intermittently. Dunno if that's your problem, but it's a cheap fix if it is!