I have a 95 eclipse rs. the check engine light and oil light come on. as far as i can determine, it only comes on when im in neutral and at a slight incline or decline. but when i put the car in gear and give a little gas, the light goes off. i checked the oil numerous times, and it is always full. what could it be? O2 sensor?

info and specs at the top of the page has the cel info. but it could be the o2 in the old days before they had heated o2 sensors when you were idling it would cool down and you would get cel because of that maybe the heater in the o2 is bad