I have RR Evoque dynamic 2012. The motor sound became harsh like it is a diesel motor. I took it to the garage and they suggested to change the timing belt. We did, but the sound did not go (I spent $2500 on this). I went to another garage but they found nothing. The computer is not showing any faults. The performance is still ok, but the sound is really annoying. When Idle it sounds like the motor will stop and very noisy. Any suggestions?