Hello guys. I need your advice on my 2007 manual jazz. It is now 217 000 mileage. And it runs so slow especially upon take off. I have replaced all 8 spark plugs with iridium but still misfiring & hesitating. Tried to uninstall the coils packs one by one and the engine starts to cough (which means the coils packs are still good right?). Does anybody know what should i do next? how about replacing the fuel filter?