Aoa I have a 1.3 civic hybrid 2006 with 200k kms on it. Got it 2 months back at a reasonable price. The car gave an average of around 14 in city and 17 in long with a medium foot. Recently it starting jerking while driving so I decided to change it's spark plugs. Went to a mechanic in f10 Islamabad and he changed 6 of the 8 coils and 4 spark plugs and charged me a lot. After that, the car is giving an average of 11 in city and 13 in long. It's speed and acceleration are also disturbed since it reaches high rpm but slowly accelerates. I went back to the mechanic and explained everything to him and he changed all 8 spark plugs to ngk to see if it would work but the car got worse (slightly jerking now at speeds around 70). Now I will go back to him but any idea why this happened? I will tell him to put the spark plugs of the model previously installed tomorrow. Could he have messed something up? I also took my previous 1.8 reborn and swift to him 2 years back and he fixed them but charged a lot so I can't comment anything on him. Any idea why the average is so low?