I tried replacing the cap, then I just removed it and that did not help at all, what you are saying sounds good but Im not sre thats the problem. I am going to hook up a universal fuel pump gauge to this thing today to try and isulate the problem to a fuel problem. I figured that since it only happens after 6 gallons of fuel used it will most definatly be a fuel issue. Hell, I have replaced everything Just at a loss. As long as it stays filled up all the way there is no problem but after 6 gallons used 140-150 miles, the problem starts and gets worse. by 180 miles you can hardly even drive the car..