I was driving my 1990 190E today and the CHECK ENGINE light came on. I don't know when it came on, but I think I might have driven about 5 miles with the light on. The 5 miles exclude the time the engine was running with the light on; I would say probably 20 minutes. The car seemed to run fine and no other warning lights came on. Prior to the light coming on, I was driving with the fuel gauge at almost empty (low fuel warning light did not come on yet). When I got to a gas station, I added about 3.38gal. of 91 octane gas from a Unocal 76 gas station. Could driving with very, very low fuel trigger the CHECK ENGINE light?

I understand it's more of an emission problem than a mechanical problem...so will driving the car with the light on cause any mechanical or electrical problems to the engine? I need my car to drive! I will take my car to the shop this week though, but I feel handicapped by this situation. I hope we are not talking about big $$$!