I've noticed recently that after shutting the car off the throttle body is making high pitched whining/buzzing noises. Immediately after shutting the car off the throttle body sounds like it is repositioning itself and the noise changes quite a bit during this process, but after it's done it continues to make a constant whining/buzzing noise. I haven't really noticed it doing this until recently, but I'm not sure if it has always done it or if this is something new and I just noticed. The car was recently having trouble idling and when letting off the throttle while driving. I cleaned the throttle body which was quite dirty as well as the MAF which helped quite a bit and it no longer is throwing a check engine light, but the idle still bounces once in a while and isn't totally smooth. I am suspecting there may be a problem with the throttle body. Anybody have input on this?