ALHAMDULILLAH... I have Vitz 2008... It is working perfect on speed... However, the car - vibrates in idle state
- the pick is slow
- white smoke comes from the exhaust when push the acceleration high
- the silencer makes noise when pushing the car on high speed

I have been to 2 mechanics who tuned several times, got oil changed... But the improvement didn't last more than a day... HELP ME PLEASE...