I just purchased a 63 series cold air intake for my 2005 Toyota Tacoma. I can really feel the difference when I step on the gas. However, at high speeds, 60 or so, I get backfire and popping in the engine compartment. I checked all the hoses and clamps and everything is tight. I went over the instructions several times making sure I did not forget any steps. I installed it just like the instructions indicated. Called K&N and they said it takes 100 to 150 miles before the computer adjusts to the high flow of air. I wanted to see if anyone has experienced problem.