I have an 81 F-250 with a 300 inline 6. The problem I have is on the carb. There is a little plate right in the back of the carb that sticks Everytime its reved up. I think the part is called the fast idle cam. Not totally sure on the name. I can push it down save it goes back to a normal idle but once its reved up again it sticks. Any suggestions on a fix?