I have a 2006 Camry 2.4l and I'm hearing a loud noise coming from the idler pulley on cold start ups when I put it in gear. I don't hear it when it's in park. The noise gets worse if you turn the a/c on. I have replaced the belt, idler pulley and top motor mount. I took the belt off and cranked it when cold and there was no noise even in gear. I can see the idler pulley moving and can confirm that's the noise but what it causing the belt to make it do that? Has anyone else had this problem? Could I have bought a defective idler pulley?

 

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