2003 Taurus Cold Weather Noise

My 2003 Taurus has a loud squeal from the engine compartment during 20 to 25 degree (F) temperatures. The sound is high-pitched like audio feedback and only occurs at about 2700 RPM. Unfortunately this is at about 70 to 75 MPH and is very annoying during highway travel. I think this is somewhere in the air intake system since it does not go away as the vehicle warms up. It does not always happen, particularly not when I get a Ford service person in the car!! One mechanic heard it but was unable to get it to repeat when I left the car with him. The problem has been there since the car was new, but has changed some. The first winter it would only happen once briefly, during initial acceleration, after the car had been parked for several hours. The following winter it became constant when at the temp and RPM above. The third winter it hardly ever occurred. The last few years it happens most of the time that the temp and RPM conditions are present. Since it only happens under driving conditions the dealers have been little help. Has anyone had, found, and fixed this one???

Is it possible the serpentine belt is showing wear? Or maybe the belt tensioner is making the noise? I had an intermittent problem with mine that made that high pitched squel. The belt was beginning to wear after 100K miles. When I changed it, the squel went away. Do you know how to check if the belt is showing wear? If not, Haynes has a fairly good manual for the car that shows what the wear looks like and how to change the belt. Good luck. Keep us posted.

I'd also suspect either the serpentine belt or one of it's pulleys - but more likely the belt because it happens in cold weather AND because if it was a bearing on, say, the idler pulley it probably would've failed by now. Kind of early for a pulley bearing to go on a 2003, I think. I just had my first failure on my '97 at 164k!

For whatever reason, I have eaten two Ford idler pulley bearing assemblies and one Ford and one Dayco (OEM) idler tensioner pulley bearing assemblies in 85k miles!?! Consider yourself lucky Colthero. They all use the same bearing and are essentially the same pulley diameter, so they should wear out about at the same time, though the tensioner bearing probably would wear out sooner as it absorbs belt and other pulsations that I have easly seen I too hear all sorts of sounds from the pulleys and belt. It's mostly the tensioner pulley on two of my Fords.

This problem, however, could be from another bearing or the inner workings of one of the accessories. The power steering pump is infamous for being noisy, but it typically makes a different kind of noise than you are describing. I've also had a nosiy alternator sound like you describe. I haven't had it, but several on the Forum have said the camshaft positioner can squeal due to a lack of lubrication believed to be due to a poor design. It is found in place of the distributor shaft.

Whatever it is, I recommend taking a three foot section of hose to use to listen for the exact location and source of the noise. You can also use a long screwdriver placed on things, listening to the handle end to locate the noise. Then there is a mechanics stethescope. I have found that each of these is better suited for different kinds of noises. The hose is the only one that you can use to listen for the noise to get louder and louder as you get closer to the noise source. You might be able to find the noisy thing at a lower rpm or idle with the listening devices, possibly avoiding trying to run the engine at high rpms.