95 Taurus 3.0 Low RPM Rattling

I have a 1995 Taurus SE with the 2V 3.0L V6. When the car is in gear or in park and the A/C is on (basically when the engine's turning at less than about 1000 RPMs), you can hear a metallic rattling noise
coming from the serpentine belt area. After about 1000 RPM everything seems normal. I was going to take off the belt and try turning the pulleys by hand to see if anything was obviously wobbly or rough, but when I tried to relieve tension on the belt by using a wrench to turn the bolt on the tensioner pulley, the bolt just turned as if it was stripped and the tension was obviously not relieved. The belt isn't obviously loose or anything. I'm not sure if this is what is causing the noise or if it's an entirely different problem. The car has 40,000 mostly city miles on it if it matters, and the belt was changed about 2,000 miles/2 year ago (the car isn't driven very much).
Any ideas would be appreciated. Thanks.
Chris
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I have a 1995 Taurus SE with the 2V 3.0L V6. When the car is in gear or in park and the A/C is on (basically when the engine's turning at less than about 1000 RPMs), you can hear a metallic rattling noise coming from the serpentine belt area. After about 1000 RPM everything seems normal. I was going to take off the belt and try turning the pulleys by hand to see if anything was obviously wobbly or rough, but when I tried to relieve tension on the belt by using a wrench to turn the bolt on the tensioner pulley, the bolt just turned as if it was stripped and the tension was obviously not relieved. The belt isn't obviously loose or anything. I'm not sure if this is what is causing the noise or if it's an entirely different problem. The car has 40,000 mostly city miles on it if it matters, and the belt was changed about 2,000 miles/2 year ago (the car isn't driven very much).
Any ideas would be appreciated. Thanks.
Chris
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key_man snipped-for-privacy@hotmail.com (95SE) wrote in message

Sorry about the post coming up twice, I posted it through Google and got an error the first time, so I thought it didn't work.
Chris
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Hey there Chris,
The rattling sound you are describing is very common on the 3.0L Vulcan I engines; It is your tensioner-arm/idler pulley which is likely the cause. Try to recreate the load necessary in 'park' to hear the rattling noise you describe. Then open the hood, and find your idler-pulley and notice the arm oscillating and causing one or two or the pin hinges to vibrate against one another.
All this is caused by a fatigued spring inside the arm, and unfortunately the spring is not available seperately, and must be purchased as a tensioner-arm. Motorcraft OEM price is about 95 bucks. Before you do that though, take a stethescope/long tubing-hose and listen to that pulley tensioner and see if the sound is coming from there. Step two would be to check the actual pulley, which autozone and the like sell for 10-20 bucks. If the bearings in the pulley are bad, then that would be the easiest problem to fix. If the pulley itself is fine, and the arm rattles, then the tensioner must be replaced.
Good luck, and please let me know how it turns out.
~B
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Thanks for the help SollyBro.
I dropped down the alternator which relieved the tension on the belt and then I took the belt off. I then took the pulley off the tensioner to see what was going on. It turns out the hole that the bolt from the pulley mounts to was almost completely stripped. The idler pulley was turning really roughly and noisily too, so I got a new tensioner(Dayco) from Murray's ($47 with lifetime warranty), and since the bearing in the tensioner pulley was still good, I took it out and put it in the idler pulley.
That noise is now gone, but I have noticed another (unrelated) problem. When I drove the car for about a half an hour then parked it (with the engine off), there was a noise coming from near the fuel filter under the car. It sounded/looked like fumes where venting, kind of like when you take off the gas cap and it hisses a bit, but for much longer, and it was a lot louder. When I opened the gas cap, it stopped. There is no visible gas leak. I'm thinking it's a ventilation thing because of that, but I don't know where the vent is. The car had been sitting for 6 months, so I guess something could have gotten clogged/plugged. Any ideas on that?
Thanks again for your help,
Chris
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Take a look at the bracket the idler pulley is attached to. There is, (at least on a 93 Taurus 3.0) a place to insert a 1/2" breaker bar or ratchet wrench. If you put the tool there you'll be able to pull the idler pulley back so the belt can be removed.

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