I have recently got an Audi A4 2.0 quattro premium with tech and sport package (about 700km). I came back from a drive on the highway about 100km and parked my car on the side road to do some errands. I was unable to start my car the usual way by pressing the start start button without inserting any key. The error i got initiallly was "no Key recognized". I then inserted the key and only got the accessory on and was unable to start the engine. I tried with multiple keys and still got the same response. After about 30 minutes of trying i finally got the car started.

So there are 2 issues here. Are there any problems with interference with the keyless ingnition? Is there a problem with starting the engine after a long drive on the highway (i.e. does the turbo engine need to cool down first?)

 

I dont' know about the Turbo, I have a 3.2. Soon after I bought the car at around 400 km, I had to at the speed of 130km/h I had to manuver around an object on the hwy and then the engine light came on. I stopped and shut down but the light stayed on. When i got home the car wouldn't shut down no matter what i did, then I just moved the car in reverse and fwd and it did shut down after that. I took the car to the dealer and they told me it was the sensor for emission. They said the sensor are set very sensetive due to the Gov't requirement. Anyway, knock on wood I haven't experienced any problems since. I have driven it a few hunderd KM at once and never had any problem starting.