new update..
I am able to achieve my normal mpg this week!! (23km/l). Actually after the fuel system cleaning, i still have a low mpg (17-18km/l) but it did improves the throttle response a bit though. After 1 week from the fuel cleaning job, i can feel the problem cameback.
The cabin still have gas smell after more than 1 week, plus i dont get the hissing sound when i open the fuel cap anymore. so i inspect the fuel filter cap and found out the rubber o-ring did not sit properly, ordered the fuel filter wrench tool and redo the fuel filter cap.
Since my brake is overdue (5yrs) i planned to change it on the same day. Upon inspection on the caliper, i noticed the caliper boot is twisted. pressed the piston in, though it feel like it kind of seized somehow, then replaced with a new pad. i drained the brake fluid a bit from the master cyclinder just right below the max line.
and that was it. my car give me the normal mpg just like for the past 5yrs im driving this car. so what's the actual problem? the injector?the fuel strainer? the brake pad?
i cant confirmed. i just hope this experince of mine can help u guys out there who having similar problem like mine to narrow down the solution and reduce the unecessary cost. peace!!