Eric Bonds

I have a 1995 Corvette base model LT1. Last Thursday morning when I went to start it, it made a screeching noise for about 10 seconds or so then quit. Friday morning it did the same thing only it lasted for a good 15 minutes or so. I looked around under the hood but I can't see anything hitting or rubbing. It almost sounds like a blower and it's hard to tell whether its metal to metal scraping or air being sucked in or blown out although I'm pretty sure it's metal scraping. Saturday evening I started it up and it didn't do it. I did hear a very high pitched and very faint whine right at the edge of my hearing, I could turn my head one way and it was gone but then I turn it back and there it is again. Whatever it is, it doesn't seem to affect performance. The car runs fine otherwise. I'm hoping someone here has had a similar experience and can point me in the right direction. Thanks in advance for any help.

ZumpC4

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Eric Bonds

I was thinking an idler pulley bearing, but I didn't think it would be that loud.

detroitrust

Did you have someone start it while you popped the hood to listen? Seems like you could narrow it down pretty quick.

ZumpC4

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Eric Bonds

That is an excellent idea, I'm ashamed I didn't think of it first. Even if it isn't making the sound at the time I'd be able to check if the pulleys were loose or turning smoothly. And in answer to detroitrust, on Friday when it lasted the longest I popped the hood and checked twice. Nothing seems to be hitting or scraping, the pulleys and the belt do wobble slightly but it's been that way since I bought it. I did have to replace the harmonic balancer twice a little over a year ago. They were both rebuilt but the first one failed after about a week. What bothers me most is the intermittent nature of it. I would think something going out would make the noise continuously.

ZumpC4

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Eric Bonds

Thanks for all the help. It turned out to be the tensioner pulley. The idler pulley was also starting to go out so I replaced them both. No more noise! Thanks again!

Railroadman

I'm late to the party but reading down the thread made me think of when mine went. Intermittent but loud, for sure. Glad you got it figured out.

Deepa

What about the ac compressor clutch?

Railroadman

See Post #8