my 84 pickup has problems! once i get her up to about 50mph she just starts surging and going flat. I havnt been able to get it to go over 60mph. <img src="/forums/images/graemlins/confused.gif" alt="" />0 to 40 mph is good to go. i thought it was the EGR valve because it had a vacuum leak but i replaced it yesterday. the vacuum leak is gone and it idles smoother but still wont go at high speed. i also noticed if i hold the throttle at about 1900-2000 rpm in nuetral, it will surge (about 100-200 drop)on its own, almost as regular as clock work(about every other second). my book says either fuel pump or air leaks. the fuel pump is a week old and i replaced the fuel filter yesterday, i cant hear any air leaks and it has all new gaskets. any ideas? thanks