The throttle return at the fuel pump is sticking, causing high idle and low speed cruise control. When the outside temps are cool there is no problem. When the truck sits outside all day with warm temps, the throttle sticks a bit. I can go under the hood and push the return back to its stop. I haven't seen this problem discussed in any forums. Is the spiral return spring getting weak? Does it need a helper? I don't know what to do. The rest of the linkage appears fine.