Hey guys i got a problem with my car reving high . My car usually idles around 900 rpms. It started afew days ago i started my car let it warm up alittle then headed down the road, now when ever i down shift and stop the car allways would idle high for a second then dump down to the normal 900 rpms now it idles at 1400 rpms and it wont drop anyways i got home shut the car off and restarted it worked fine idled at 900 rpms but this problem has been showing up more often. Anybody with any sugestions please post. Could it be an idle sensor or something like that.