when i rev my truck up the rpms go high and fall slowly back down to idle. i have an exhaust clip and when i rev it i rev it up then take my foot completely off of the gas. you can hear it hold up high then drop down slow. Any ideas as to why it does this?

http://www.youtube.com/watch?v=-aNZO...e=channel_page

 

i had a simmilar problem and it turned out to be the throttle position sensor on the side of the throttle body. theres a walkthrough on the diy thread about how to clean the sensor.. just drill a small hole in the body and spray in some electrical cleaner. worked for me.