Well...not that its going to matter...but...my JEEP (2000 XJ) was making a similar sound about 2 weeks ago...I mail ordered an idler pulley to have ready. About a week later, I had power steering fluid spilled all over the driveway. So...for the folks that might use this as a troubleshooting tool...you do NOT necessarily need to assume it is the idler pulley!

 

To me, the OP posting the resolution or final outcome of the problem is the most important part of the thread. Besides, who wants to read 20 or 30 posts in a thread and not find out if the problem was resolved? This time, it’s pretty apparent that the idler pulley is the problem, but that’s not always the case. While searching for info on the CPS, I found a thread where the OP detailed an issue with his engine not running right. Recommendations for resolving it started out with fuel system or fuel injector checks, then turned towards looking at ignition or electrical systems. Turned out it was a broken valve spring. If the OP hadn’t posted this valuable piece of information, it wouldn’t be considered in future troubleshooting efforts.