Inconsistent "Service Engine Soon" Light
I have a 2001 BMW 325i, with approximately 55,000 miles. Has had the 30,000 Inspection I, and is due for Inspection II soon, but I only drive it occasionally, so the mileage does not accumulate quickly. "Service Engine Soon" light has gone on and off for several weeks, but not consistently - sometimes is on, then off the next time the car is driven. The car sounds and runs normally - no performance issues whatsoever, no major issues for 7 years. Advice?