Racking Sound

:banghead:My jeep grand cherokee has developed a racking sound in the front part of the engine when in idle state but disappears when i rev up the engine. I suspect my timming chain must be lose or something, does anyone know what the cause is and how to resolve it?:runaround:

what year is your Jeep and what engine do you have, and how many miles are on it? If you want to isolate the sound, take your drivebelt off and start the truck. If the noise is still present, then it could timing chain and/or gears. If it goes away when you take off the best, you could have either a bad auto tensioner or idler pulley.