the yellow check engine sign came on today while i was on the freeway....i took it immediately to the dealer...he said that the fuel mixture sensor was "out of specs" and that it needed to be fixed....he told me to bring the car in on monday...i asked him if its ok to drive the car with the check engine sign on...he said its perfectly alright in this instance because the computer on the car will adjust for the sensor problem...i don't know if he's right or not...the car is not in limp mode or anthing...i have a trip this weekend but i don't know if i should take the clk or my other car...please advise...is it ok to drive or is the dealer wrong....thanks in advance