i own civic 1997 exi , done 91000 still in genuine condition, i mean never visited any mechanic except oil change etc. from the last 2 day i am obseving that the car is not maintaining its idle speed . i think its idle speed should be 0.8 but it is maintaining 0.3-0.4 . at nights once all lights get on its RPM decreases more. i have changed its plugs and air cleaner but no fruitful result is obtained so far . plz help me out