why is my car idling erratically

any check engine light or fault codes? my first guess is a vacuum leak. check the vacuum elbow in front of the intake manifold i've seen them crack a few times. cleaning the throttle valve may help some. has the battery gone dead, been replaced or jumped recently? sometimes the throttle basic settings lock up and need to be reset (stored a throttle error code).

hi dont know if this will help but had the same problem with my 2.4 v6 a4 and i spoke to a freind whom told me to clean the throttle housing which on my car worked perfectly after it was cleaned but my rev counter fluttered all the time to the point where it would die but have had no problems since it has been cleaned its got to be worth a try at least