high pitched squeal noise under the hood - driving me nuts!

[dontaskwhoiam2001]

Dear all,

My car is a 1996 i30, 50k miles only, I bought it used from dealer one month ago.

I recently noticed a high pitched squeal noise from under the hood. It is not too loud but noticeable when I drive. Here are some details of this problem:

- The noise starts as long as I press brake to slow down during driving, the noise disappears almost right away when i press gas from brake. The noise remains even if I press brake to a complete stop.

- This is an intermittent problem. It seems that the noise happens more easily when I start driving for the day, which means that the problem often occurs when the car is cool.

- I sent the car to a technician. I shifted to "R" and braked to a complete stop, the noise occurred. He then opened the hood immediately, the very noticeable noise was from the idler pulley area. He adjusted the idler pulley. The noise disappeared for the day, but started again the next day.

- He told me that I might have to replace the idler pulley and drive belts. I then had him replaced the idler pulley and the two drive belts with genuine Nissan parts yesterday, it was all fine for the day. But this morning, I got the noise back again. However, i did not hear the noise this afternoon though.

Any one can shed me some light on this weird thing?

Thanks a lot in advance!!

jack

[FoxFire]

wd-40 the bearing area..

then go get some anti belt sqeal goo at autozone(little packet of grease stuff usally at the front counter area )

[Sentientbydesign]

I highly recommend that you DON'T use the WD-40 on your bearings.

Here are the reasons why:

WD-40 is a low viscosity lubricant. It works extremely well at breaking up higher viscosity lubricants (like bearing grease).

I have the same car as you and my Idler Pulley was making noise, so I sprayed it with WD-40 and the pulley flew off while driving on the freeway.

Maybe one of the other belt driven accessories is locking up like the A/C or alternator...etc.

[dontaskwhoiam2001]

Thanks FoxFire.

[dontaskwhoiam2001]

Thanks Sentientbydesign. I am not sure I can handle this, I also feel that it is a waste of time to get my technician check it again.I may have to go to the Infiniti dealer's service dept and ready for a big bill.

[huyqvu]

mine was doing that. they might have over tightened the nut that holds the pulley. that will prevent it from moving freely.

[dontaskwhoiam2001]

that sounds simple, I can check it myselfthanks

[NutriaforBreakfast]

Can you buy an automotive stethoscope and listen for it?

[dontaskwhoiam2001]

This is a quick update on this problem -

I called the mechanic and told him that I still got the noise even after replacing the drive belts and idler pulley. He asked me to take it back. He then adjusted the nut on the idler pulley. It has been two days since then and i have not heard any noticeable noise any more. I guess the problem has been fixed

thank you all again

jack