Hello Everyone,
I bought an 04 Mazda 3 about 3 or so months ago. I bought it with 48,000 miles on it. Just a couple of weeks ago I noticed a funny sound coming from the belt. It sounds as if the belt is loose and squealing. I took a quick look, belt seems tight, as do pulleys. This noise started when it became very cold(daily highs of 0F, overnight lows of-15F). Its back up into the mid-30's now but sound still occurs. Is this a sign that I may need a new belt? Or an adjustment? What would it cost to get a new belt installed? I'm a new Mazda owner so any info would be great. Thanks.

 

you can inspect your belt using a hand-held light source, if both side of the belt look smooth, it's not your belt. Also with the light source, you can examine all the pulleys when the car is running (be very careful), to see if any wheel is vibrating. My guess is that it might be the belt tensioner pulley.
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ANAFLAVORLATIN

 

Is there a way someone can check the tightness of those pulleys at home? Are they just torqued down with some sort of a mounting bolt?

 

it could be the bearing (part of the pulley) that's making noise.
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Avandia Lawsuites

 

He means the idler pulley and that's quite possible that the bearing has gone bad or is dry and is about to (go bad.)
As far as belt tension, there is a tool that attaches to these new fangled serpentine belts that measures tension in lbs/sq.in. using deflection. I have personally not checked into (seen a service manual) that states that there is another way (i.e. torque @ the idler/tensioner adjustment.)
Is your 3 still under warranty? <4yrs/<50k miles on the clock? If so, take it into your nearest dealer and have them look at it. You don;t have to have them actually do any repairs but they might help diagnose the problem for you.

 

I know there was a TSB before on the idler pulley...because it made a funky sound. Id have them check into that!

 

Hmmm. Now that you mention it, so do I. I never had the problem w/mine so I never took it in for that TSB.

Hmmm. I just looked over the whole list of TSBs for all years and can't find it, but as I'd said, I seem to recall (no pun intended) something about this also....?