Hi, my 2009 Rondo LX 2.4L has been acting lately and sometimes not starting on the spot, it takes 4 to 5 tries with me pressing the gas pedal... I took it to a mechanic, he said that nothing is wrong even though my check engine light is on. Anyways i did use the thing to check why (check engine )is on and it gave me a code for the Intake valve. i checked the valve pulled than put it back on. the light went off then came back on. Does it mean that i have to replace the Valve? and should i change the plugs? My car has a 160.000 KM (Canada).