@Vaqas :- definately i get this problem . i first thought it to be tuning , but since this might also be a problem , i will check it out .
@Tanveer_1 :- R u sure it should be done that soon ?? i thought to do it after every 5 years ?? . If oil is present in cylinder then i am sure gas too will be filled less . Then after every 4 months do u get low gas filled in ur cylinder ??
@hash4u :- what should be the average time when we should get our cylinders from where . Is it done from any cylinder fitting shops or from Hydro carbon institute of Pakistan ??