Screaching noise, what could it be?

[bluebombersfan]

The higher I rev the louder it gets, the belt is almost new looking so I don't think it is that, I rubbed a piece of soap on it and didn't stop it so for sure it must not be the belt. I am assuming most likely alternator or steering pump?
Also what is worst case scenerio if I leave it like this, something will cease and the belt would snap?
Will I still be able to drive home if something ceased and the belt snapped? I would assume it would be okay excecpt I would loose alternater and power steering.

 

[infantry grunt]

I had a squeeling noise once,only in the cold season,my distributorshaft.If its coming from the front,take the belt off and try checking for play in your accessories,and check how freely they move.Good luck

 

[infantry grunt]

Oh,and if its not coming from the front of your engine,the pilot bearing in your fly wheel(assuming its a stick)will squeel too,you san determine this by engaging/disengaging your clutch,in neutral

 

[Rowdy Fitzgerald]

Could be ac pulley or Alternator going bad or a bearing in the block.

 

[armadillon]

Pulley bearings sound so good when they go. My 91 miata had some fun there. Sounded like Ted Nugent.

 

[stmitch]

If it's coming from the back of the engine, it could be the cam synchro failing. Very common on the 3.0, especially as the miles increase. If it doens't get replaced, the synchro will eventually go out completely, and when it does your oil pump will stop, likely seizing your engine. There have been TONS of 3.0's that were ruined just like this. If your sound is coming from the rear of the engine, I'd replace the cam synchro asap.

 

[Earl43P]

^^^What he said!

Remove the serp belt and start it just long enough to hear whether the noise is still there. 20 seconds or so.

You CAN'T DRIVE with a broken serpentine belt. It'll overheat and crack expensive heads.

 

[MA Ranger]

Check the EGR valve too. It'll scream like a banshee when it goes bad. Easy, low-tech way to check if it's the source of the noise is to put a piece of sheet metal between it and the opening on the upper intake that it connects to (where the gasket is). No noise with the sheet metal in place = bad EGR. Hope this helps.

 

[bluebombersfan]

Looks like its the alternator

I ran the truck with no belt for about 20 seconds and couldn't hear any squeeking, so I felt relieved as it's not the cam synchro thing. But I did hear squeeking when I turned the alternator by hand. Must be the alternator. Even so I am surprised that it squeeked under hand pressure, because in the past I found that they only squeek when turned quickly by the motor. Is there anyway of squirting some oil or something? Or just get a new and be done with it? Also I think I could hear a very faint grinding noise guess that's not good either.

 

[RANGER760]

The cam position synchronizer would cause the check engine light to come on. Your lucky if all you've got to replace is the alternator. Eventually it'll stop turning, I'd recommend just getting a new one, especially if it's grinding.

 

[bluebombersfan]

so then if this cam synchro thing were actually falling apart then there would be many signs before the engine would actually seize then? 3 things would happen from what i understand, 1 the screaching, 2. engine light would go on, and 3. my guess the oil light would go on aswell? If I am correct then with all these signs it would be easy to save your motor from siezing catastrophy?

 

[Lack Thereof]

The cam position synchronizer would cause the check engine light to come on. Your lucky if all you've got to replace is the alternator. Eventually it'll stop turning, I'd recommend just getting a new one, especially if it's grinding.

If the bushings are going out you can get squealing with no check engine light. The light will only come on if the shaft is wobbling enough to interfere with the operation of the sensor mounted on top - you would probably also get a random misfire once it got to that part.

The shaft is quite thick, as thick as an old distributor shaft. It would have to be stuck quite badly to actually break - typically they just tear the crap out of the bushings and develop a bad wobble. But if it did break, your engine would stop running immediately as well as losing oil pressure. Without the cam position sensor signal, the computer cannot time the engine at all. It would be like a sudden ignition point failure on an older vehicle.

 

[bluebombersfan]

I thought it was the alternator

I replaced the alternator thinking it was that. I know it's not the cam synch because I ran the engine with the belt off for 1/2 a minute and could not hear the squeal.
The Problem now is it's so hot here were I live (Winnipeg Manitoba), that it just doesn't squeal, when it gets colder that's when it will come back and I can try to re-diagnose things as I don't think it was the alternator.