Advice needed for serious engine whine

[Owali]

Can someone tell me if my diagnosis is correct? I am getting some serious whining noise from my engine. It is incredibly loud, like nails on a chock board screech. Strangely, the noise is only audible when my A/C is running. The noise sounds like it is coming from my alternator, not my compressor though. This makes me think my alternator is going bad.

I should also mention that a brand new compressor was put in a couple of years ago. The voltage gauge is reading 14V, and the A/C blows cold air. I just finished replacing my A/C tensioner pulley, A/C belt and alternator belt, which was done to eliminate another whine (or so I thought, the previous noise was never this bad and was present with the A/C off). After changing those parts, I drove around for a while with no noise until I turned the A/C on.

I am very confused now. The only other thing I can think of is maybe my belt tension is not correct. Does anybody have any ideas?

 

[Rtype1206]

I'd check the tension again...Had a similar problem and rechecking solved it

 

[Larry Bastanza]

I would go back and have a careful look at the A/C pulley assembly. Loosen it, then remove the nut, dish washer, and washer. Make sure these items are in place just as I mentioned. I have seen the washer end up in the wrong place.

Look here:

http://www.acuraautomotiveparts.org...omp=List All&vinnoT=&trim=&trans=&view=normal

Note the parts installation of parts #16-#21. I had mistakedly put #20 outside of #18 once, by the nut(#21), sure sounds familiar.

Regards,
LarryB

 

[alverman]

I had exactly the same symptoms last summer. It was the A/C compressor. It had been renewed only the year before. After removal I found very small metal particles in the compressor body and therefore think it had been best I didn't use the A/C at all anymore. I had no option but to replace the compressor with another one.

 

[Owali]

FIXED!!
I listened to the noise more carefully this morning. This time my wife had to help me out. She toggled the A/C on and off while I watched and listened. I noticed that when the A/C engaged, the rotation of the belt would decrease, but the compressor was turning at a faster rate. That one piece of information would have helped us all diagnose it yesterday, I just didn’t notice it then. Anyway, I just increased the tension of the belt and it went away, I guess there is a sweet spot. It sounded like the noise was originating from the alternator. But I guess the sound is bouncing around everywhere in the bay, so it is hard to pinpoint. I have never heard a slipping belt before, but now I know.

Thanks for the help everyone! :biggrin: