Hi, everyone. I have a yaris. There are two problems annoyed me so much. Sometimes when I use the first gear I could hear graunching noises. Also, graunching noises could be observed between first and second gear change. This problem does not always happen but have 30% chance. Secondly, everytime when I start the car and move it use the first gear, I could hear a metal knock sound from the bottom of the car, probably underneath the engine area (especially the cold engine start). If I do not switch off the engine, the issue does not happen again. However, after switching off and restarting, yes, I could hear the metal sound again. Last service, I told the problems to the toyota. The mechanic had a test drive and also heared the graunching noises but he said it is very difficult to locate where the problem is. SO, what are these problems? What should I do? Thanks a lot.