I am facing strange problem. At cold start if I rev engine upto 2000 to 2500 RPM,I am getting whistling noise & too much poor throttle response. I know that FIAT has suggested not to expect good throttle response but I am getting too much poor throttle response & whistle at cold start. But noise disappears after keeping engine idle for 2-3 min. First I thought whistling noise is due to leaky turbo. But whistle is disappearing after warm-up of engine. What may be the reason.