Isaac,

As far as im concerned, the OBD codes once stored, are kept until cleared or erased either by faulty wiring, battery failure/disconnection etc. Once the check engine light comes on, it SHOULD store at least one code... My best guess is maybe worn wires or bad contacts on the OBD system itself, not the actual engine issue (hopefully there wont be anything!)

Car running alrite? Sometimes its better to just ignore the stupid light, especially if no codes come up... Take it from me, my 92 244 has the SRS light on ALL THE TIME! My bulb failure light is almost always on (though all lights work etc.)

Best of luck!

Spencer
92 244 187K