I forgot to put the engine oil cap back after topping off the oil due to the stupid "yellow engine light" that came on for the 200000 times (my dealer told me it was fixed last time I brought my car in, obviously they didn't know what they were doing in the service department). Without knowing that the cap was missing, I drove about 30 miles or so and the "sevice engine soon" light came on. I then drove another 300 miles until I finally realized the cap was missing. Today my car is getting the first oil change service at a different dealer and the service advisor told me I may have to pay $112 to get the SES light reset. He said the mechanics will have to run some kind of diagnostics just to find out what's wrong. If the SES light came up because I was driving it without the cap, is it as simple as just resetting the light? Have I done any real damage to the car? Please help.