High pitched noise.

[Davids68F250]

Ok, maybe someone can help me with this one. Sometimes I get a very high pitched, constant sound coming from my engine compartment, but I can't pinpoint it. What's wierd is when it does it.

I can start the truck up in the morning and run it as long as I want without it making the noise, but if I shut it off, and restart it, the noise will begin, and stay going for the rest of the day basically. A couple times, I shut the motor off and restarted it, and the noise went away. Sometimes it doesn't make it at all. It is very annoying.

I think it has something to do with vaccum, but I can't pinpoint where the noise is coming from. It's too high pitched, and it sounds like its coming from a lot of different places at once.

Any ideas? Thanks.

[reflectionpoint]

This is probably totally off base but my truck made a similar high pitched noise recently--so loud I almost thought it was in the wheel bearing or something (even though it was the wrong type of noise for that) and it ended up being the speedo gear on the transmission. It happened to me when it was cold and went away after a restart when the truck had been driven a little ways.

The vac leaks I've had on my truck sound like hissing and were fairly straightforward to locate, for what it's worth. An odd one was the brake booster 'cause the sound was only in the cab, but not under the hood--which seemed weird but also helped me to pinpoint it in short order

[FORDification]

Often an alternator or water pump bearing that's starting to die will make that noise. It's easy to diagnose...just remove the belt that drives each one and start it up to see if the noise disappears.

[1971ford]

Alternator or belt??

[fordman]

bad alt bearings
too loose of a belt
or power steering pump noise.
sounds like a possible bad or loose belt.

[quantumleap]

i agree with keith..check the water pump..when they go..sometimes the bearings make a high shreiking noise...that or check your belts (on the motor..not your pants)..haha

[bb429power]

Often an alternator or water pump bearing that's starting to die will make that noise. It's easy to diagnose...just remove the belt that drives each one and start it up to see if the noise disappears.

I was going to say the same dang thing. Both would do it, I've had both happen to me.

[Davids68F250]

This is outrageous. Today when I was driving it, it happened, so I was out to find the culprit. I had a plastic tube to try to pinpoint the noise. It was coming from the front of the carburetor. I busted out the carb cleaner to find a vaccum leak. As soon as I sprayed the fuel line inlet into the carb, the sound went away and stayed gone. Hopefully for good. Anyone ever heard of this before?

[fordman]

no i haven't. that couldnt have fixed anything. but it sure told you the problem area.

[70_F100]

Sounds like you've got a problem in the front of the carb.

If there was a problem with the fuel inlet, you would have a leak.

Keep looking, you're in the right general vicinity!!!

[bb429power]

Yes i have, there was a video on youtube where the guys carb would squeal and then pop and fire would come out.

[DiamondGBar87]

My Oldsmobile does something similar, but it sounds like its supercharged when it does it! I'm fairly certain its a vac leak, but it does sound kinda cool when it does it.