My brother had around 1/2 years old mehran in 2015, it had same problem, giving fuel smell both on CNG and petrol. I have mehran now 2017, same issue it has. Got checked it by experienced mechanic, no improvement, everything is told to be ok. Two days back i drove my friend's mehran, same issue it had.
This product of highly inferior quality has this BUILD-IN problem in every Mehran I drove or sat in. Problem is not of things went wrong but actually problem is in its manufacturing. How strange that the best selling stupid car has health issue. Paki Suzuki must be sued for damages. I or my brother never bought mehran but using them only as they are officially provided to us.