New noise from engine

[VetteOwner]

hmm yes all good suggestions so far.

ive heard powersteering pumps make weird noises especially when it sucks up a bubble (low fluid)

could be belt, could be alternater

somehting else it could be since you say it does it and goes away with temps is a vacuum leak, partially cracked hose can cause a whistle or a whine sometimes, or it could have popped off. this would be my best guess.

its obviously somehting engine driven or engine itself so just check anything that roatates

[GasSavers_JoeBob]

A leaky vacuum hose? I had a somewhat similar noise in the Geo, and it turned out to be a collapsed vacuum hose, vibrating.

[VetteOwner]

Originally Posted by JoeBob

A leaky vacuum hose? I had a somewhat similar noise in the Geo, and it turned out to be a collapsed vacuum hose, vibrating.

yea sucks in air in small cracks causes a hell of a noise or can do what you said. kinda like the ol blade of grass between your thumbs

[theholycow]

Originally Posted by VetteOwner

kinda like the ol blade of grass between your thumbs

My wife described the sound exactly that way.

[bobc455]

Originally Posted by theholycow

That's two votes for alternator

Make that three. I'm not guaranteeing, but as best I can tell with the poor quality recording and playback it sounds like an alternator.

And while we're at it, add one vote for forced induction. A supercharger on that would be fun.

-BC

[Jay2TheRescue]

A supercharger on that would be fun.

-BC

CORRECTION: A supercharger on that would be a lot of fun.

[kamesama980]

something driven by the belt. Most likely the alternator.

[theholycow]

I happened for a few more days but never dependably enough that I could stop and touch stuff with the mechanic's stethoscope while it was still happening. It hasn't happened at all in a few days.

I guess I'll have to wait for it to return and get worse before I can diagnose it.

[GasSavers_JoeBob]

The vibrating vacuum hose problem I had came and went in a similar fashion...

[JanGeo]

It is the alternator with the bearing running out of lubrication it will make noise when the belt is cold and tighter putting more load on the bearing and once it warms up the lube will move around and quiet it down and the belt will stretch a little. The Alternator is the only belt driven device that is geared up to a higher RPM while everything else is slower or about the same speed as the crank. Check for dust around the bearings as well as any play in the shaft of the alternator then you can loosen the belt and try spinning the alternator by hand and see if it feels a little bumpy - that will tell you right away.

A far stretch would be the starter motor gear not returning from the flywheel.