I have a strange rattling sound that sounds kind of like a loose v-belt only it's not. It appears when the engine is warm and it follow the rpm. I did a few quick 0-100 km/h today and it really started to rattle. After driving slowly the rest of the way home, I parked the car and let it idle for a minute or two and then the noice slowly went away. Then when revving the car there is nothing to hear. Now that I think about it; The noice might be more like a ball berring that's starting to get noisy. What could this noise be? I tried to locate and it just might come from the right side of the engine (passenger side in LHD car) but definately not confirmed.
Impreza WRX 2.5 '08 with about 35.000 KM on the clock.
Let me know what you think.