Ok this is kinda weird.. The other week my car started making this noise.. If i rev the engine when the revs are coming down I hear a fairly loud whinning sound, almost like a super charger would make when it is whinning down.. It also does when im driving... When im slowing down for a stop sign it also does it, and when I accel. but it stops after 30.... Anybody know what this could be..Timing chain maybe?? I would have thought something to do with the tranny but it does it when it's in park and I rev it up...

 

Make sure all accessories are tight along with the alt fan. Check to see if the water pump shaft has any side play.

 

So where's it coming from? Front of the engine? Bottom rear? Top? etc.

Once you've narrowed it down to a general area, go get a piece of heater hose and stick it up your ear (I just love telling people to do that!!!) and use it like a stethoscope, probe around with the other end of it until you find where it's coming from.

 

It's coming from the front of the engine somewhere, I have a car stethescope and im going to try that when I get home tonight.. Thanks morley I'll check that too..

 

well it's coming from the inside of the alternator.

 

Well you've answered your own question now I guess. You will need a new alternator as probably you have bad diodes and it is creating an electrical interference which makes the whining sound.

 

Ok, I found out that the bearings are about to go out in the alternator, but on my way home it stopped.. It doesn't do it anymore.. weird... Im gonna let it cool for a little bit and crank it up to see if it is still doing it..

 

Doesn't matter if they're still whining or not when you get home, they're still fornicated.

Get a new alternator. Wasted bearings don't grow back like fingernails or something.

 

Time for a rebuild kit.

 

I know they don't fix themselves I was just saying that it stopped making the noise.. I was on my way home from picking up a new alternator...

 

besides heater hose, you could use a stethascope, or a peice of metal. Just use your hand as a cup over your ear.

 

Did someone touch a sensitive subject? You sound as if you were literally offended.