High pitched humming when engine on on 2002 Ford Escort

Increasingly loud high pitched humming is causing concern. Gets good mileage, over 100,000 mi, I bought it with about 20,000 on it. No knocking, pinging, all fluids topped up and hoses okay....

2 answers 3 comments
Does the noise increase with engine speed? Vehicle speed? Have it checked out, it could be many things, but it could be a warning that if left unchecked, could cause more damage, like a bearing in the timing belt tensioner or water pump.
It DECREASES when I acellerate. The hood is bent in and held on by a bike lock until I have time to go to junk yard and purchase new hood and spend half a day at junk hard unbolting & rebolting new hood. It is not unsafe, not totally safe, but hood bangs on engine when I drive on frway, it could be a hose that is getting hit, dented and re-ruptured, but there was different sound before I replaced hose, this is high pitched whine, fact that it does go away when I accellerate and that still getting good mileage, no change in engine temperature or power seems like positive. I have very little money, where should I take it for honest, cheap inspection, surely not dealer?! I am in S. Cal. near San Diego.
This sounds like a possible wheel bearing.

Check the shop directory for a shop in your area. http://repairpal.com/directory
i got exacr same thing ,high pitched whime that decreases woth acceleration. what was the cuase,,,a senser,intake manifold leak.becuase no exhuast when throttle is engaged
Sitting at the Ford dealership reading this post and they called me up to tell me what the problem is. My 2001 Isuzu rodeo has a (high pitched) whining. They said it was a bearing for one of my pullies/belts. $200 to fix which was a lot less than I was thinking. I can get more info if you need it once they are done.