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Rasping noise when accelerating

My 97 Mazda Protege ES (I think–it’s a manual) produces an awful noise when I give it gas, usually as the RPMs climb. When in neutral there’s no problem, but it’s particularly bad in first gear. When on the highway it’s a less-pronounced constant.

I can’t tell the direction it’s coming from…tomorrow morning I’m going to pop the hood and give it some gas in neutral to see if there’s any effect. Maybe give you some better specs.

The noise sounds like a rasp…or an angry alligator! My fluid levels all seem to be normal, but it kind of sounds like something’s not lubricated.

This sounds like yet another case of a loose heat shield.
Have it checked when the car is up on the lift for its next oil change.

However, I just can’t help shaking my head over one statement in the original post, namely:
“I think it’s a manual”.

How can a car owner not know if his car has a manual transmission or an automatic transmission?

I believe the phrase “I think–it’s a manual” refers to the ES designation, as in “It’s an ES, I think. It’s a manual.”

In addition to a loose heat shield I would consider an exhaust leak as another possible source for this noise. The flex pipe, perhaps, opening as the engine shifts under acceleration, especially in first gear.

Please let us know what you discover when you open the hood.

Sorry for the confusing sentence structure. My roommate read over my shoulder and made the same comment as VDCdriver…the car is a manual, and I was speculating on the ES classification.

On popping the hood and giving it gas…

The noise seems to be coming from the left side of the engine (when facing it), and could possibly be originating from the belt that’s located directly behind the dip stick. It’s loose, and makes a little thucking noise, but that’s not the one I had noticed. When I give it gas, or rather, more gas than it should get, a horrible “HHHNNUUUUUUUUUUUUSSSSSS” starts up, and is coming from the same area as the belt. It really sounds like something is running dry–almost like a piece of sheet metal is being dragged across concrete.

Now, I’m definitely going to get the belt fixed…but can that awful noise be coming from a loose belt? Or the gears associated with it? It’s not a squealing noise…more like a dry, rasping moan. And it’s louder than I would think a belt could produce.

When in neutral, or even when it’s getting just a minimal amount of gas, I don’t notice the noise. The belt “thucking,” yes, but not the rasp.

Based on the location where you have localized the noise, I would suspect that the bearings in your belt tensioner and/or idler pulley are doing dry. If they seize up while you are driving, you will lose the belt, and you may wind up being stranded and in need of a tow. As a result, I would suggest taking the car to your trusted mechanic very soon in order for him to check those bearings.