@ehsaniuk
Thanks a lot.I also have heard about gap cng but haven't tried him yet. If you are talking about that "Khattak Ustad" in defence area (don't remeber the name of station as there are 2 side by side) , he was the 1st one I visited for cleaning and tuning and he ruined it. All I got after spending 6 hours and 400 rs was prolonged starting, more consumption and high leakage from kit. The worst thing was when I got home and try to start it in the evening, it refused. Then I went to Shams in shell cng near board (he is also good) and he fixed all the problems charging me 1100rs (major work in the kit). No problem in 3 months till now.