I was at idle for about ten minutes , when i put it into drive ,nothing happened! no acceleration not even an idle change! So i slammed the brakes and put it in park, then pulled it back down to drive and it ran sluggish ,and it had no power when i hit the gas. so i pulled over popped the hood ,i thought maybe vacuum , i was at a 1/4 tank of fuel and the filter was changed about two weeks ago! it hasnt happened agian! what could it be?