Yeah that problem is a big headache I have the 1998 7k carburetor engine (Automatic) and it stalls a lot too after vibration. I think Toyota has played out all the townace (KR-42) buyers worldwide by giving a 7K carburetor engine instead of a 7K EFI engine. It does only 4km per liter. If somebody has a solution for this problem please comment. And the only way you could get the gears to change fast is by releasing the accelerator go for 1/5th of a second until the gear changes.