Carbonization process:
Here some machanics who usually face kindof problem(Chocked injectors) carbonised injectors by some manual way...They got some small fuel setup in which they force petrol through injector in continuation which cleans up the effected injector...
Its better to buy a injector cleaning bottle and mix it up with fuel recommended on bottle lable. It will clean you injectors...
Carbonisation process may harm injectors if not done by an expert... so i recommend you to buy a injector cleaner bottle which will cost you around Rs:150/- ... You can buy it from Plaza if you live in Karachi...