Salam, guys i am not a professional in cars but i want to discuss my problem here.
i own a santro car, i used it for about 4 years and no problem at all, but abt 3,4 months back i got its cng kit serviced from township hyundai centre. and after that my car is doing missing on cng. i went to them 2 times and they just tighten a screw from the engine front near rpm and race wire. but it starts after 2,3 weeks again car starts missing.. i want to know what it can be..
p.s there is always a sound from the rpm device placed in enging front of santro sort of like a (ggheeeeeeeeeeeeeeee) sound 
shall i replace the rpm device..
and i also wanna know do they (hyundai dealers) offer genuine parts or they are just capturing money, they changed my cars cng filling valve in 3600 and when i conformed price from out market it was of only 300, 400. and i was so annoyed that they took thousands more from me.. also they are asking to change the rpm in 6700 which from out market is also of 600,700..
please guide me well coz i am not much knowledged in these matters..
and is that a matter of engine now, coz my car is driven 100,000kms+ and is accendited..
