OH NO! MY Truck!

[bamonkey]

Im pretty mechanically inclined (or reclined) when it comes to vehicles but 2day my truck just barely started up. It sounds like tight or bad pulleys but i dont think thats it cuz i just replaced them. When i step on the gas it sounds like pressure is building (like your lungs) when i shut it off it reeeeaallly makes a hiss so im really confused.. if any u had this b4 and can help it would be appreciated.. im posting this on everyboard i goto