A car has what's called sensors! When there's something wrong with the engine of your car then the "check engine light" will come on! This light or sensor informs you that u need to go have your car checked,b/c something is wrong! Most people overlook that light b/c they don't see or feel a problem when that light comes on. POINT: STOP overlooking the LIGHT & go get a spirit check b4 if out of commission. THINK!