Vibration on idle & rough start

[Murtaza_murti]

Hi, guys. I wanted to ask on how to fix the vibration on idle and rough start problem in my '06 Belta (1KR-FE, 1.0L I3).

The thing is that, since a few months I've been facing vibration on idle on D/N/R while the car is stationary. Their isn't any vibration while driving the car. Sometimes the vibration completely vanishes and sometimes it vibrates hardly.

The second thing is that I've been facing rough start problems since about two weeks, whenever I start the in the morning it would stall on the first start. Then when I start it on the second try it would start normally and perfectly. I am having doubts on the fuel filter, and I am planning on getting it replaced pretty soon I just wanted to see what the experts here would recommend before I do something.

Note: I've recently changed the spark plugs, added a bottle of STP super concentrated Fuel Injector cleaner on the last tank top-up. The car is 31,000Kms driven haven't faced any problems other than these since I've imported it back in 2007 when the reading on the odometer was 18,000Kms.

Thanks to everyone in advance, happy motoring!