/// The first place to look is the timing belt. Check the tensioner. You can release the nut to allow the spring to force the idler bearing forward, through a rubber plug in the timing belt cover. If you have not replaced the timing belt and do not have the history do it now. I fix everything when I go in, all belts, seals, timing belt. I had a neighbor do my belts and timing belt after I had back surgery. He did not replace the crank seal. "It wasn't leaking," he said. It is now.