How do you ppl control Air, for the CNG, in my car if i block the air, it works perfectly fine on CNG but on petrol it does hell of knocking and driven sluggishly. if I open the air petrol become fine with very little knocking but it shuts of as soon as switch to CNG mean it dont work on CNG, I have got it tunned from many places including computerized tuning and from Hundai work shop as well. when air is controlled and on CNG RPM behave rough for some time on idle and on signals. same as it is breathing heavily.
what are the suggestions from the experts no back fire issue. throttle is cleaned, tappets are adjusted plugs are new, 56000K on the odo model is 2008. i need it work perfect on petrol as well as CNG without any knocking.