I am trying to troubleshoot a CEL light that comes on from time to time staying on for a week then going off. What I notice is that the air/fuel guage stays lean for a long time (abnormal) then after the car is running for a while it will toggle back and forth (normal). My question is:
when the lights indicate lean, does this mean that the ecu is detecting more gas? Also, when it goes green or rich does it mean it is running more air. WOT the light is green so I would assume that indicates rich.
I am just trying to use this meter to help direct me toward the failing sensor.
THX...