I bought a 2005 Lexus RX 330 used a couple of months ago from a dealer. It has an automatic transmission and 137k miles with few problems so far. But in the last month, I've noticed a high pitched squealing noise coming from the area near the serpentine belt whenever the engine is running. The previous owner changed the belt 9 years ago and the belt doesn't appear to be cracked at all. But the belt is getting old and the owners manual says to replace it after 10 years or 120 k miles. Is it likely that my belt is causing the problem (squealing noise) or is it something else (water pump, tensioner, etc.) associated with the belt? The replacement cost for a belt is quite high so I want to diagnose the problem correctly. Thanks!
Take off the drive belt and start the car, if the noise goes away, then you have some accessory making noise.
Follow what the manufacturer calls for when it comes to timing belts.
Idler pulley bearing failure. They are the weak link in the system.
Belts get contaminated and also "dry" out...way past due to be changed.
No shortcuts...change everything...belt, idler pulleys, and tensioner. Any of those fail, slings the belt, you're calling a rollback.
