The Nissan Path

Hello everyone, this is my first post.My mom purchased a 2004 nissan pathfinder from a used car dealership about 6 months ago. Recently, the engine has been squealing very loudly on cold starts and goes away after the engine has warmed up enough. So far Ive replaced the power steering pump, idler pulley, alternator, fan clutch, and belt. However, this morning my mom told me it was squealing again. I have no idea what it could be now. From my research these were the most common causes of the problem but ive also read it could be the harmonic balancer or water pump. My dad told me when he removed the belt and started the truck the noise went away. It sounds like its coming from the passenger side so i dont think its the ac compressor or the other idler pulley.Any help would be greatly appreciated. Thanks

Couple of things:

-All belts are not created equal. Major belt suppliers like Dayco and Gates make both cheap and premium belts. Genuine Nissan belts are always the best to use and most of them are made by Bando or Mitsuboshi. Bando belts can be purchased from Napa and Federated Auto Parts and are usually the best choice on the aftermarket as they tend to fit better than some of the choices from Dayco or Gates. If your only choice is Gates or Dayco, go with their premium belts.

-Check your belt alignment between the pulleys and look for wobble or side to side deviation while the engine is running, which would be an indication of an alignment issue or play in a bearing.

-Look for dry rot splits or missing pieces of rubber if the harmonic balancer is a two-piece design. Using a mirror can be helpful when doing this.

-Get a solution of approximately 5% detergent and 95% water in a spray bottle and spray the belt while it is squealing. If the noise goes away when you spray it, the problem is between the belt and the pulleys. If the noise stays the same, you are likely looking at a mechanical issue, like a bad bearing.

-Make sure the belts are properly tensioned (adjusted). Over-tightening the belts can cause noise (and other problems) just as much as much as belts that are too loose.

The belt I purchased was a Dayco. It was the best one available at Autozone but Im not sure if its from their premium line of belts. I thought it might have been loose so I just tightened it. Ill check the harmonic balancer and do the spray test tommorow. Thanks for the advice.

If it was the Dayco premium belt, it would have said "Poly-Rib" on it. Dayco has a video to help pinpoint and correct noises:

http://www.rockauto.com/catalog/moreinf ... cc=1431977

So the noise is gone. Tightening the belt seemed to do the trick. Thanks again for your help.

So the noise came back again. i took the belt off and started it again, no noise. This leads me to believe that the last thing left on this belt could be the culprit, whis is the fan pulley bracket and fan pulley. There is a bearing on the fan pulley bracket that that i hope is whats making the noise. Ive purchased thesr two parts and will replace them soon. Ill update afterwards to let everone know how it goes. The alignment of the pulleys looks good too. Thanks again for the help.

Did the parts fix your problem?

OK, tightened mine and the squeal is gone as well. Easy job.