Hi clublexus fam,

this morning when I started my is250, I realised a loud whining noise. I have attached a video. I have read some forums saying it's normal but normally it is no where near as loud. Some people say it's the alternator whilst some says it's the belt. Has anyone had the same experience? What was the problem?

Thanks

 

You need to have the pulleys checked. Mine was the tensioner pulley causing similar noise.

 

Maybe the water pump?

 

what did you do to fix it? Did you have to replace anything? Also, I'm not sure if this will help, but the whining sound gets louder as I accelerate.

 

Doesn't sound like a water pump. Maybe an alternator? Tensioner? Pulley?

 

I replaced the water pump and the alternator and still have the whine. Next up is the tensioner pulley. I've had the whine for years and car drives no different than before

 

Another possibility? A/C compressor? Does it change when you switch the A/C on/off?

 

Yes, sound more like AC compressor

 

Swap out the accessory belt first and see if that helps. Definitely part of the accessory drive system.

 

Am really sorry and thankful I didn't listen to what the mechanic said at first! It was the alternator causing the noise, not the tensioner pulley.

Good luck