Whining/screeching from serp/timing belt area

[SHOPLUS]

I've owned the car for about 2000 miles now and it has been doing this since I've been driving it. Its my first SHO and I love it but this noise gets annoying. I thought it was the serp belt tensioner pulley but a $50 bearing later it still makes the same noise. I thought maybe alternator but that screech on decel doesnt sound like a ford alternator whine to me.

My other thought is an over tensioned timing belt. I had read
"To check and reset the tension on the belt with the timing belt covers installed, you can take off the small door from the lower timing belt cover, loosen the 14mm nut about 1/2 turn, rotate the crankshaft at least two full turns in the clockwise direction only until the first, yellow mark (60 degrees before top dead center on the number 1 cylinder) aligns with the "0" degree index mark on the lower timing belt cover (this causes the greatest slack on the tensioner side of the timing belt), retighten the 14mm nut 25-37 lb-ft and reinstall the door. "

Is this a safe way of checking?

Here is the noise by the way

 

[shopartsnw]

If I have a difficult time isolating a bearing whine, here is what I do.

I start by removing the serpentine belts and running the car. If the noise goes away, you know it is in the serpentine system and you can further work to isolate it to an accessory or tensioner.

If you still have the noise with the serpentine belts removed, you know those parts are fine. At that point it is usually a timing belt tensioner bearing or something rubbing.

This is only for diagnosis, and you should not run your car for extended periods without the serpentine system.

Hope that helps

Mike

 

[kevinspann]

My guess might be a timing belt tensioner, but do what Mike said.

Also, looks like the car has underdrive pulleys on it

 

[SHOPLUS]

Yeah i suppose that would be a good first step before i go playing with the timing belt. I have no idea what stock pullies look like. My SHO was the first sho I've ever seen and ive only seen one on the road since owning it so i couldnt tell you if it has UD pullies.