Does anyone here ever encountered an idling problem usually around 1200 to 1400 rpm range while at the same time the check engine indicator illuminates. Is this related to a dirty fuel line/fuel filter,injectors or it has something to do with my cars timing belt/tensioner. My car btw is a lancer 97 model (pizza pie) already at 185,000 km reading. I've already had my oil change, sparkplugs and even added a cyclo "fuel/injector cleaner" so to clean the fuel line and injectors but still the same problem. My last timing belt/tensioner change was when the car was at 85,000 km. What might be the problem here for I never encountered such probem before. Hoping for your advice.