Rough idle / check engine soon light
 

had a real rough idle in my 2002 3.0 x5 this morning where it felt like it was really going to hurt the pocketbook. it sat for about a week or two since lately we have been favoring the 3 series convertible and i guess it got a clogged fuel injector or something. took it around the block really fast and then down to the auto parts store for some fuel injector cleaner. seems to have solved the problem for now. other posts here talk about bad gas and sitting for a few days is the cause of this problem. looks like it was my problem as well. it sure did feel like a serious problem since that idle was really rough and the whole car shook and sounded horrific. thank goodness at least for now it was only another minor diy fix. whew!