Replaced serpentine belt and idler pulley today to stop this noise. Nothing changed but we eliminated anything near the belt. Tensioner had been replaced two years ago. Loud squeal starts slowly after starting then builds. It's constant and seems to come from the top of the engine where there are no turning parts. Both fans are running OK. Noise is synched with spinning of the engine.
It's a 3.0 liter V6, vintage 2003. Appr. 63,000 mi. Any guesses?

 

with engine cold take off serpentine belt and run engine for a few minutes.
if squeal disappears suspect alternator bearings are dry.
otherwise it could be the dreaded cam syncro..

 

Thanks for the reply. I have concluded it is indeed the camshaft synchronizer. Videos on YouTube are helpful. Some people are bad mouthing the Dorman replacement product which is 1/3 the price of the Motorcraft synchronizer. My local AA Parts has the Cardone brand for 1/2 the price of Motorcraft. Doubt if I'll pay for M'craft for a '03 Taurus.

 

If you have the Vulcan 3.0L engine, the cam sync, located toward the upper rear of the engine, where the distributor used to be, is a good suspect.

DON'T continue to drive it this way, as if its shaft siezes, breaks, or strips the gears, the engine oil pump will also stop operating, so there goes the engine!!!!!

If you replace this part yourself, pay close attention to proper sync alignment with the #1 cyl at TDC on the compression stroke. Most autoparts stores have an alignment/tool fixture available in their "Loan-A-tool" program, for a refundable deposit.

DON'T use Dorman replacement parts, use Motorcraft.

Let us know how it goes.

 

By all means stay away from Cardone.

 

I appreciate the helpful replies. Just one respectful question: Isn't the Motorcraft camshaft synchronizer made off shore just like Dorman and Cardone parts?

 

Probably so. I'd trust the Dorman piece before I would the Cardone. Dorman is new, Cardone is a rebuilt unit.

 

If your of a mind to use something other than Motorcraft, maybe first have a read here, Alert! Dorman Cam Synchronizer Assembly! - Taurus Car Club of America : Ford Taurus Forum