Update....
My car was having below issues
1. In lower grades or when you brake the car, or when put it in 1st gear and picks it up, that ghar ghar kind of sound was coming from engine side. Specially when ac is on.
Car was suddenly shutting of while running even on high speed. It was not ignition issue as dashboard lights etc. were still lit.
Car was having a bit of jerks while moving.
I went to a guy near muukka chowk, Karachi and he scanned my car using a device. He said car needs tuning. He took out plugs (which I recently changed) and got them cleaned again. Plus he cleaned throttle body and other sensors ( I remember one i.e. the one placed inside air filter box). Throttle body was quite dirty.
Result
Ghar ghar sound completely gone and car is running quite smoothly even when the ac is full on.
I drove the car after service for around 50 km but it didn't shut of.
Jerks or missing also gone.
That guy was in a view to also replace fuel pump. He said that the scanner showed a bit of problem in fuel pump. But he also suggested me to drive the car after tuning and if problem remains, then he will changed the fuel filter. But all three problems are now gone for now. I'll drive it for couple of other days and seen if problem comes back or not. Specially shutting off during driving.
The name of that guy is Farooq. He charged me Rs. 2000 for tuning and scanning. Rs. 500 for scanning a d Rs. 1500 for tuning (throttle body and sensors cleaning) but I am happy that the ghar ghar sound is gone completely. Car was heavy on ac but now running quite smoothly. And so far didn't shut of.
I'll continue driving it and will update.